This subtopic is seeking small business - non-profit research institution partnerships to advance subsystem elements of three important, next generation in-space propulsion technologies:  the Electrostatic Solar Sail, Freeform additive fabrication for propulsion elements, and Nuclear Thermal Propulsion low cost fuel testing.

Scope Title

Electrostatic Solar Sail (E-Sail) Advancement

Scope Description

The E-Sail is a propellant-less in-space propulsion system that utilizes electrostatic repulsion of solar wind (off of an electrically biased tether) to generate thrust. Preliminary studies indicate several advantages of this technology, including enabling access to interstellar space with transit times significantly faster than state-of-the-art (SOA) technologies. For this year's E-Sail investments, concepts to advance the Technology Readiness Level (TRL) of the E-sail guidance, navigation, and control system and/or robust models for spacecraft dynamics both during deployment as well as during operation are solicited. Marshall Space Flight Center (MSFC) is currently conceptualizing a 6-12U, ~10km total tether length E-Sail demonstration. Neither a specific architecture nor specific requirements have yet been detailed, however, responders should focus efforts in their proposed work towards this size spacecraft while keeping eventual scaling to as much as a 10x larger spacecraft in mind.

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, and/or Research

Desired Deliverables Description

Phase I proof of concept and/or preliminary guidance, navigation & control (GN&C) designs and/or models that will lead to Phase II medium to high fidelity prototypes ready for system infusion (in case of hardware), system analysis (in case of models), and/or advanced TRL testing (space environments testing) to support a MSFC led technology demonstration mission. Beyond Phase II, infusion into the planned E-Sail Technology Demonstration Missions (TDM) via a Phase III, IIE, directed work, etc. or additional development/test via an Announcement of Collaborative Opportunity (ACO) may be potential opportunities.

State of the Art and Critical Gaps

The E-Sail concept has potential to enable practical access to interstellar space and fast travel beyond our solar system. The E-Sail has several open technology gaps. NASA is systematically reducing known risks of full system implementation prior to a flight demonstration. State of the Art GN&C systems and modeling have limitations due to the complex and changing dynamics of an E-Sail system. A critical gap is robust and high fidelity GN&C modeling and/or concepts for control of the E-Sail vehicle. 

Relevance / Science Traceability

An Electrostatic Sail E-Sail is a propellant-less advanced propulsion system that harnesses solar wind by electrostatic repulsion. Note, this contrasts Solar Sails, which utilize optical reflection of solar photons. E-Sail is comprised of thin tethers, which are electrically biased to form large electric fields. These fields create a virtual sail that repels solar ions and generates thrust. A key advantage is this mechanism better maintains thrust as it moves away from the sun – falling off at only 1/distance, substantially better than the solar sail 1/d^2. E-Sail will rapidly improve transit time within and to the edge of the solar system as well as enable out of plan maneuvers not currently possible.

References

https://www.nasa.gov/centers/marshall/news/news/releases/2016/nasa-begins-testing-of-revolutionary-e-sail-technology.html [20] (as of 8/2/2019)

Scope Title

Large Scale Freeform Additive Fabrication using GRCop-42 and Gradient Alloys

Scope Description

NASA is interested in soliciting proposals to develop a process for large scale freeform fabrication using additive manufacturing of GRCop-42 and functional gradient materials. Components such as rocket nozzles and heat exchangers are actively-cooled with internal channel features and require high performance materials in the extreme environment. Typically these components are made from a monolithic alloy, although various alloys and functional gradient materials could increase performance and optimize the overall system. The objective of this solicitation is to complete process development (i.e., directed energy deposition, coldspray, etc.) to fabricate a freeform component that incorporates thin-wall integral channels into a structure. This process should focus on GRCop-42 (Cu-Cr-Nb) and transition to an alternate material using a functional gradient process. The proposer should provide a technique and approach to axially transition from the GRCop-42 to alternate alloy (Superalloy, Stainless, High Entropy Alloys) providing a compatible functional gradient joint to minimize stresses. A thorough development approach would include process development, initial characterization and testing of the GRCop-42 and functional gradient alloys, process demonstration of manufacturing technology demonstrators (MTD), and trade study and/or planning to increase the scale to several feet in diameter.

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, and/or Research

Desired Deliverables Description

Phase I: Develop a process for fabricating (using directed energy deposition, coldspray, etc.) a freeform structure that incorporates thin-wall integral channels targeting a heat exchanger, combustion chamber, rocket nozzle, channel-cooled structure and provide a trade on combination of compatible materials, with NASA inputs.

Leading to Phase II: Complete fabrication of process development samples using GRCop-42 and functional gradient alloys (Superalloy, High Entropy Alloys) to change the material axially along the component; and complete process characterization, mechanical testing, materials evaluation to provide first order design data. Fabricate manufacturing demonstrator components with integral channels with materials selected. Provide components that NASA could perform benchtop, flow, and/or hot-fire testing. Demonstrate a manufacturing technology component with integral channels and that is larger than 16” diameter with the GRCop-42 and functionally gradient alloys. Provide scale-up to >40” diameter.

State of the Art and Critical Gaps

NASA has been developing various additive manufacturing technologies in GRCop-42 using laser powder bed fusion (L-PBF) and currently working to mature large-scale (>3 ft dia) blown powder directed energy deposition (DED) process using NASA HR-1 and JBK-75. These technologies have been limited to monolithic materials though. Additional development has included bimetallic cladding (radial deposition) to provide superalloy jackets on copper-alloy combustion chambers under the Low Cost Upper Stage Propulsion (LCUSP) project, however this technology is not easily accessible at service companies. While the technology exist to fabricate components at sizes <16” diameter using laser powder bed fusion (L-PBF) using GRCop-42, this is limited to a monolithic material in the axial direction. There are also no current additive techniques to rapidly fabricate GRCop-42 structures larger than this scale.

There are also additional challenges in this approach with a binary transition from one alloy to another. Optimized structures for heat exchanges and combustion devices would include the ability to fabricate large structures with complex internal features and vary/transition alloys along the axial length of a component (not just radial). This would allow for a more compliant bond between a copper-alloy and alternate material instead of a drastic change in alloys. This would reduce risk of joints. A further gap is the ability to produce copper-alloys, such as GRCop-42, in scales larger than 16” diameter. This provides new solutions for designers of large engines and structures providing higher thermal margins on the walls with the use of copper. The copper technology using additive manufacturing does not exist using directed energy deposition (DED) or other technologies at this scale.

Relevance / Science Traceability

Applications to: Propulsion and energy, Liquid rocket engines, Small thrusters, Additive Manufacturing, and Advanced Manufacturing.

References

Gradl, P., Greene, S., Wammen, T. “Bimetallic Channel Wall Nozzle Development and Hot-fire Testing using Additively Manufactured Laser Wire Direct Closeout Technology”. 55th AIAA/SAE/ASEE Joint Propulsion Conference, AIAA Propulsion and Energy Forum. August 19-21, Indianapolis, IN. AIAA-2019.

Gradl, P., Protz, C., Wammen, T. “Additive Manufacturing Development and Hot-fire Testing of Liquid Rocket Channel Wall Nozzles using Blown Powder Directed Energy Deposition Inconel 625 and JBK-75 Alloys”. 55th AIAA/SAE/ASEE Joint Propulsion Conference, AIAA Propulsion and Energy Forum. August 19-21, Indianapolis, IN. AIAA-2019

https://gameon.nasa.gov/projects/rapid-analysis-and-manufacturing-propulsion-technology-rampt/ [21]

Gradl, P. “Rapid Fabrication Techniques for Liquid Rocket Channel Wall Nozzles.” AIAA-2016-4771, Paper presented at 52nd AIAA/SAE/ASEE Joint Propulsion Conference, July 27, 2016. Salt Lake City, UT.

Scope Title

Nuclear Thermal Propulsion (NTP) Advancement fuel testing

Scope Description

The NTP concept is similar to a liquid chemical propulsion system, except instead of combustion in the thrust chamber, a monopropellant is heated with a fission reactor (heat exchanger) in the thrust chamber and exposes the engine components and surrounding structures to a radiation environment. NTP thrust is ~25,000 lbf with ~29 lbs/sec flow of hydrogen through the fuel elements. Current fuel element designs are based on cermet (ceramic metal) or carbon with low enriched uranium.

The scope is open to university/Small Business Concern (SBC) partners to propose key innovation on how to best test NTP fuel pieces in the university nuclear reactors that come close to meeting the following test goals:

• Neutron/gamma radiation fluence approximating NTP operation.
• Heat NTP fuel test piece up to 2700K.
• Power density of 5 MW/L.
• Test piece exposed to hydrogen (if possible).
• Maintain steady state up to 15 minutes (or fluence equivalent).

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, and Research

Desired Deliverables Description

The STTR team provides the following for Phase I and II:

• Irradiation capsule design and thermal analysis predictions to handle a variety of fuel test pieces in the university reactor.
• Instrumentation required to determine how best the fuel performed and validate analysis predictions.
• Development plan for Phase II including a description of the reactor test arrangement and fuel pieces to be irradiated. Start-off with irradiating a surrogate test piece during phase II. Conclude phase II with irradiating a fuel test piece with High Assay Low Enriched Uranium. Include a description of post-test examinations to be performed.

State of the Art and Critical Gaps

Testing various fuel concepts in the same environment as an NTP engine at low cost is not easy. Many current irradiation test facilities can test sample pieces to only a few of the NTP environment conditions.

Relevance / Science Traceability

Research could have a significant positive impact on the design and development of NTP systems.  NTP potentially useful for both science and exploration missions.

References

Multiple publicly available references, see for example:

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20120003776.pdf [22] (as of 9/30/2019)

https://apps.dtic.mil/dtic/tr/fulltext/u2/a430931.pdf [23] (as of 9/30/2019)

Scope Description

This subtopic seeks technologies related to cryogenic propellant (e.g. hydrogen, oxygen, methane) storage and transfer to support NASA's space exploration goals. This includes a wide range of applications, scales, and environments consistent with future NASA missions. Such missions include, but are not limited to upper stages, ascent and descent stages, refueling elements or aggregation stages, nuclear thermal propulsion, and in-situ resource utilization. Anticipated outcome of Phase 1 proposals are expected to deliver proof of the proposed concept with some sort of basic testing or physical demonstration. Proposals shall include plans for a prototype and demonstration in a defined relevant environment (with relevant fluids) at the conclusion of Phase II.

Desired technology concepts are listed below in order of priority:

• Develop cryogenic mass flow meters applicable to liquid oxygen and methane, having a volumetric flow measurement capacity of 1 - 20 L/min (fluid line size of approximately ½ inch), of rugged design that is able to withstand launch-load vibrations (e.g., 20g rms), with remote powered electronics (not attached to the flowmeter), able to function accurately in microgravity and vacuum environment, and having measurement error less than +/- 0.5% of the mass flow rate reading. Ability to measure bi-directional flow, compatibility with liquid hydrogen, and ability to measure mass flow rate during two-phase flows is also desired. Designs that can tolerate gas flow without damage to the flowmeter are also desired. Goal is Proof of concept end of Phase 1. Working prototype flow meter end of Phase 2.
• Broad area cooling methods for cryogenic composite propellant tanks (reduced and/or zero boil-off applications or liquefaction): Design and integration concepts must exhibit low mass, high-heat transfer between cooling fluid and propellant in tank, high heat exchanger efficiency (>90%), and operate in reduced gravity environments (10-6 g worse case). Proposers should consider structural and pressure vessel implications of the proposed concept. Target applications include liquid oxygen liquefaction system (16 g/s neon gas, 85K < T < 90K, pressure drop < 0.25 psia, 2.6m diameter, 3m tall tank) and reduced and/or zero boil off liquid hydrogen nuclear thermal propulsion system (3.5 g/s helium gas, 20K < T < 24K, 7m diameter, 8m tall tank).
• Cryogenic liquid/vapor phase separators capable of delivering single-phase liquid flow at least up to 10 gallons per minute, void fractions up to 30%, with an emphasis on minimizing pressure drop across the separator. Devices should be able to maintain performance (phase separation at highest flow rate) after multiple (> 15) thermal cycles (room temperature to 77K and back). Phase separator should tolerate transient (transfer line and separator are chilling down). Phase 1 concept should yield a proof of concept using liquid cryogens. Phase 2 should focus on minimizing phase separator pressure drop, overall integration of phase separator into transfer system (i.e. where to route the vapor), and development a unit to test in liquid hydrogen.  

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

References

1. Johnson et al. “Investigation into Cryogenic Tank Insulation Systems for the Mars Surface Environment” 2018 Joint Propulsion Conference Cincinnati, OH, July, 2018. Paper.

2. Plachta, D., et al. "Zero Boil-Off System Testing" NASA TP 20150023073.

3. Hartwig, J.W., "Liquid Acquisition Devices for Advanced In-Space Cryogenic Propulsion Systems" Elsevier, Boston, MA, November, 2015.

Expected TRL or TRL range at completion of the project 2 to 4

Desired Deliverables of Phase II

Hardware, Software

Desired Deliverables Description

Phase I proposals should at minimum deliver proof of the concept, including some sort of testing or physical demonstration, not just a paper study. Phase II proposals should provide component validation in a laboratory environment preferably with hardware deliverable to NASA.

State of the Art and Critical Gaps

Cryogenic Fluid Management is a cross-cutting technology suite that supports multiple forms of propulsion systems (nuclear and chemical), including storage, transfer, and gauging, as well as liquefaction of ISRU (In-Situ Resource Utilization) produced propellants. STMD (Space Technology Mission Directorate) has identified that Cryogenic Fluid Management (CFM) technologies are vital to NASA's exploration plans for multiple architectures, whether it is hydrogen/oxygen or methane/oxygen systems including chemical propulsion and nuclear thermal propulsion. Several recent Phase IIs have resulted from CFM subtopics, most notably for advanced insulation, cryocoolers, and liquid acquisition devices.

Relevance / Science Traceability

STMD strives to provide the technologies that are needed to enable exploration of the solar system, both manned and unmanned systems; cryogenic fluid management is a key technology to enable exploration. Whether liquid oxygen/liquid hydrogen or liquid oxygen/liquid methane is chosen by HEO (Human Exploration and Operations) as the main in-space propulsion element to transport humans, CFM will be required to store propellant for up to 5 years in various orbital environments. Transfer will also be required, whether to engines or other tanks (e.g. depot/aggregation), to enable the use of cryogenic propellants that have been stored. In conjunction with ISRU, oxygen will have to be produced, liquefied, and stored, the latter two of which are CFM functions for the surface of the Moon or Mars. ISRU and CFM liquefaction drastically reduces the amount of mass that has to be landed.

Scope Title
Reactor and Fuel System

Scope Description

The focus is on highly stable materials for nuclear fuels and non-fuel reactor components (i.e., moderator tie tubes, etc.) that can heat hydrogen to temperatures greater than 2600K without undergoing significant dimensional deformation, cracking, or hydrogen reactions. Current technology hurdles related to ceramic metal fuels center around refractory metal processing and manufacturing (i.e., welding of refractories, refractory metal coatings, etc.). The development of refractory alloys with enhanced/targeted material properties are of key interest (i.e., tungsten or molybdenum with increased ductility, or dispersion strengthen Mo/W alloys). Current technology hurdles with carbide fuels include embedding carbide kernels with coatings in a carbide matrix with potential for total fission product containment and high fuel burn-up. Manufacturing and testing of the insulator and reflector materials are also critical to the success of a Nuclear Thermal Propulsion (NTP) reactor.

Technologies being sought include:

• Low Enriched Uranium reactor fuel element designs with high temperature (> 2600K), high power density (>5 MW/L) to optimize hydrogen propellant heating.
• New advanced manufacturing processes to quickly manufacture the fuel with uniform channel coatings and/or claddings that reduce fission product gas release and reactor particulates into the engines exhaust stream.
• High temperature fuels that build on experience from AGR (Advanced Gas Reactor) TRISO (Tristructural-isotropic) design and testing. Potentially enable NTP with Isp> 900 seconds.

Fuels focused on Ceramic-metallic (cermet) designs:

• Fabrication technique for full length W/UN or W/UO2 fuel elements with greater than 60% volume ceramic loading

Fuels focused on carbide designs:

• Compatibility with high temperature hydrogen.
• High thermal conductivity and other properties (e.g., ductility) needed for high power density operation (~5MW/l).
• Kernel diameters, including coatings for fission product containment, which allow the fuel element to be fabricated with adequate strength for high temperature and high-power density operation.

Insulator design (one application is for tie tubes and the other is for interface with the pressure vessel) which has very low thermal conductivity and neutron absorption, withstands high temperatures, compatible with hot hydrogen and radiation environment, and light weight.

Expected TRL or TRL range at completion of the project: 2 to 5

Desired Deliverables of Phase II

Prototype hardware is desired.

Desired Deliverables Description

Desired deliverables for this technology would include research that can be conducted to determine technical feasibility of the proposed concept during Phase I and show a path toward a Phase II hardware demonstration. Testing the technology in a simulated (as close as possible) NTP environment as part of Phase II is preferred. Delivery of a prototype test unit at the completion of Phase II allows for follow-up testing by NASA.

Phase I Deliverables - Feasibility analysis and/or small-scale experiments proving the proposed technology to develop a given product (TRL 2-3). The final report includes a Phase II plan to raise the TRL. The Phase II plan includes a verification matrix of measurements to be performed at the end of Phase II, along with specific quantitative pass-fail ranges for each quantity listed.

Phase II Deliverables - A full report of component and/or breadboard validation measurements, including populated verification matrix from Phase I (TRL 4-5). Also delivered is a prototype of the proposed technology for NASA to do further testing if Phase II results show promise for NTP application. Opportunities and plans should also be identified and summarized for potential commercialization of the proposed technology.

State of the Art and Critical Gaps

The SOA (State-Of-the-Art) is reactor fuel developed for the Rover/NERVA program in the 1960's and early 1970's. The fuel was carbon based and had what is known as "mid-ban" corrosion, which effected the fuel endurance. Switching over to cermet (metal and ceramics) or advance carbide fuels shows promise, but has fabrication challenges.

Solid core NTP has been identified as an advanced propulsion concept which could provide the fastest trip times with fewer SLS (Space Launch System) launches than other propulsion concepts for human missions to Mars over a variety of mission years. NTP had major technical work done between 1955-1973 as part of the Rover and Nuclear Engine for Rocket Vehicle Application (NERVA) programs. A few other NTP programs followed including the Space Nuclear Thermal Propulsion (SNTP) program in the early 1990's. The NTP concept is similar to a liquid chemical propulsion system, except instead of combustion in the thrust chamber, a monopropellant is heated with a fission reactor (heat exchanger) in the thrust chamber and exposes the engine components and surrounding structures to a radiation environment.

Focus is on a range of modern technologies associated with NTP using solid core nuclear fission reactors and technologies needed to ground test the engine system and components. The engines are pump fed ~25,000 lbf with a specific impulse goal of 900 seconds (using hydrogen), and are used individually or in clusters for the spacecraft's primary propulsion system. The NTP can have multiple start-ups (>4) with cumulative run time >100 minutes in a single mission, which can last a few years. The Rover/NERVA program ground tested a variety of engine sizes, for a variety of burn durations and start-ups with the engine exhaust released to the open air. Current regulations require exhaust filtering of any radioactive noble gases and particulates. The NTP primary test requirements can have multiple start-ups (>8) with the longest single burn time ~50 minutes.

Relevance / Science Traceability

STMD (Space Technology Mission Directorate) is supporting the NTP project.

Future mission applications:

• Human Missions to Mars
• Science Missions to Outer Planets
• Planetary Defense

Some technologies may have applications for fission surface power systems.

Scope Title
Ground Test Technologies

Scope Description

Included in this area of technology development needs are identification and application of robust materials, advanced instruments and monitoring systems capable of operating in extreme temperature, pressure and radiation environments. Specific areas of interest include:

• Devices for measurement of radiation, pressure, temperature and strain in a high temperature and radiation environment.
• Non-intrusive diagnostic technology to monitor engine exhaust for fuel element erosion/failure and release of radioactive particulates.

Expected TRL or TRL range at completion of the project: 2 to 5

Desired Deliverables of Phase II

Prototype hardware is desired

Desired Deliverables Description

Desired deliverables for this technology would include research to determine the technical feasibility during Phase I and show a path toward a Phase II hardware demonstration.  Determine a prototype instrument arrangement which can be strategically positioned to monitor NTP operation as good as possible. To monitor fuel degradation in the exhaust stream, the optimum position of the sensors must account for anomalies near an operating reactor core and have the ability to withstand the radiation and heat environment. Testing the technology in a simulated (as close as possible) NTP environment as part of phase II is preferred. Delivery of a prototype test unit at the completion of phase II allows for follow-up testing by NASA.

Phase I Deliverables - Feasibility analysis and/or small-scale experiments proving the proposed technology to develop a given product (TRL 2-3). The final report includes a Phase II plan to raise the TRL. The Phase II plan includes a verification matrix of measurements to be performed at the end of Phase II, along with specific quantitative pass-fail ranges for each quantity listed.

Phase II Deliverables - A full report of component and/or breadboard validation of sensor measurements, including populated verification matrix from Phase I (TRL 4-5). Also delivered is a prototype of the proposed technology for NASA to do further testing if phase II results show promise for NTP application. Opportunities and plans must also be identified and summarized for potential commercialization of the proposed technology.

State of the Art and Critical Gaps

The SOA NTP ground testing involved open air testing in the 1960's and early 1970's. The current regulations require an exhaust treatment system to avoid release of significant quantities of fission products into the air. Validating various exhaust treatment concepts requires a subscale simulation of NTP hot hydrogen, the cooling system, filtering, and special instrumentation to monitor what is coming out in the hydrogen exhaust, which could lead to shutdown.

Solid core NTP has been identified as an advanced propulsion concept which could provide the fastest trip times with fewer SLS launches than other propulsion concepts for human missions to Mars over a variety of mission years. NTP had major technical work done between 1955-1973 as part of the Rover and Nuclear Engine for Rocket Vehicle Application (NERVA) programs. A few other NTP programs followed including the Space Nuclear Thermal Propulsion (SNTP) program in the early 1990's. The NTP concept is similar to a liquid chemical propulsion system, except instead of combustion in the thrust chamber, a monopropellant is heated with a fission reactor (heat exchanger) in the thrust chamber and exposes the engine components and surrounding structures to a radiation environment.

Focus is on a range of modern technologies associated with NTP using solid core nuclear fission reactors and technologies needed to ground test the engine system and components. The engines are pump fed ~25,000 lbf with a specific impulse goal of 900 seconds (using hydrogen), and are used individually or in clusters for the spacecraft's primary propulsion system. The NTP can have multiple start-ups (>4) with cumulative run time >100 minutes in a single mission, which can last a few years. The Rover/NERVA program ground tested a variety of engine sizes, for a variety of burn durations and start-ups with the engine exhaust released to the open air. Current regulations require exhaust filtering of any radioactive noble gases and particulates. The NTP primary test requirements can have multiple start-ups (>8) with the longest single burn time ~50 minutes.

Relevance / Science Traceability

STMD (Space Technology Mission Directorate) is supporting NTP project.
Future mission applications:

• Human Missions to Mars
• Science Missions to Outer Planets
• Planetary Defense

Electric propulsion for space applications has demonstrated tremendous benefit to a variety of NASA, military, and commercial missions. During recent flight thruster development projects, NASA has identified manufacturing issues that have resulted in significant costs to achieve performance repeatability and hardware reliability. Without addressing the process and materials issues, both the production of existing thrusters and the development of new thrusters will continue to face the prospect of high costs that limit the commercial viability of these technologies. NASA thus seeks proposals that address improved fabrication processes or materials to reduce the total life cycle cost of electric propulsion thrusters. For example, a proposed component or assembly manufacturing process that improves fabrication reliability could permit reductions in the scope of acceptance testing and thus lower the overall cost of the technology.

Critical NASA needs have been identified in the scope areas detailed below. Proposals outside the described scope shall not be considered. Proposers are expected to show an understanding of the current state-of-the-art (SOA) and quantitatively (not just qualitatively) describe improvements over relevant SOA processes and materials that substantiate NASA investment. Prospective proposers in fields outside of electric propulsion are highly encouraged to apply if they have experiences with manufacturing processes that may be suitable for this solicitation.

Scope Title

Material joining in hollow cathodes

Scope Description

SOA hollow cathodes in thrusters are complex assemblies with metal-to-ceramic (e.g., alumina, magnesium oxide, etc.) and metal-to-metal joints where dissimilar materials may have large thermal expansion mismatches. In such cathodes, operating temperatures can range from 1000 - 1700 °C (necessitating the use of refractory metals such as molybdenum, rhenium, tantalum, tungsten, etc.), and material joints must be able to survive in excess of 10,000 thermal on-off cycles without failure. Existing material joining processes used to construct Hall-effect and ion thruster cathodes have demonstrated inconsistencies in joint strength and the presence of impurities that may degrade cathode performance during vacuum operations. Efforts to mitigate these issues have to date contributed to the high cost for the integrated cathode assembly and thruster; thus, making them less attractive for commercial usage, particularly for small satellite propulsion applications. Proposed material joining processes to this area must be compatible with critical high-temperature materials; be performed readily, reliably, and with some economy; demonstrate structural integrity at typical cathode operating conditions; and avoid contaminant release that could degrade the performance of common cathode emitter materials such as barium oxide (BaO) and lanthanum hexaboride (LaB6).

References:

• M.J. Patterson, "Robust Low-Cost Cathode for Commercial Applications", NASA/TM 2007-214984.
• AWS C3.2M/C3.2:2008, "Standard Method for Evaluating the Strength of Brazed Joints".

Scope Title

High-temperature electromagnets

Scope Description

Thermal management of integrated electric propulsion systems is often challenging, especially for compact micro-propulsion devices or high-power-density systems. For thrusters with electromagnetic coils, such as Hall-effect thrusters or plasma thrusters utilizing magnetic nozzles, these magnetic circuits may experience operational temperatures in excess of 500 ºC due to coil self-heating and close proximity to plasma-wetted surfaces; such magnetic circuits, may also need to survive in excess of 10,000 thermal on-off cycles without failure. High wire packing density is frequently desirable to achieve high magnetomotive forces (i.e., high ampere-turns). This is facilitated by small wire diameters with thin insulation, with the drawback of being more susceptible to heating and insulation failure. Existing processes for manufacturing and potting magnetic wire have exhibited instances of insulation and potting degradation during thruster operations that can lead to early thruster failure; however, the associated extensive acceptance testing required to ensure high reliability contributes to the current high cost of thrusters. Proposed solutions to this scope area must be compatible with high ampere-turn, multi-layer electromagnets; be fray-resistant; and avoid performance degradation at the operational conditions indicated above. Any formation of volatile materials under operational conditions, particularly if binders or potting materials are used (e.g., for electrical insulation between wire layers or for thermal management), must be limited so as to preserve the insulating materials' dielectric strength and to remain compliant with general NASA material outgassing guidelines (i.e., < 1% total mass loss and < 0.1% collected volatile condensable material).

References:

• J. Myers et al., "Hall Thruster Thermal Modeling and Test Data Correlation", AIAA 2016-4535.
• ASTM E595-15, "Standard Test Method for Total Mass Loss and Collected Volatile Condensable Materials from Outgassing in a Vacuum Environment".

Scope Title

Robust ceramics for Hall-effect thruster discharge channels

Scope Description

State-of-the-art Hall-effect thrusters make use of hot-pressed, hexagonal boron nitride (BN) or derivative ceramics, for the machined discharge channel in which plasma is generated and accelerated. The discharge channel (typically with outer diameters between 2 and 14 inches depending on the thruster's power level) must maintain electrical isolation between the thruster electrodes while being subjected to an energetic plasma environment, large thermal gradients and transients, and back-sputtered material from other thruster components or the vacuum test facility. To date, these materials have exhibited substantial lot-to-lot variability in key material properties (including mechanical strength, moisture sensitivity, and thermal conductivity and emissivity) that have resulted in discharge channel damage during vibration, shock, and thermal testing of the assembled thruster. Such material property inconsistencies have thus necessitated costly thruster design features to improve survivability margins against mechanical and thermal shock. Proposed processes to improve the lot-to-lot consistency should focus on the BN family of materials or similar ceramics compatible (i.e., exhibiting low ion-bombardment sputtering yields) with a Hall-effect thruster's discharge plasma.

References

H. Kamhawi et al., "Performance, Stability, and Plume Characterization of the HERMeS Thruster with Boron Nitride Silica Composite Discharge Channel", IEPC-2017-392.

ASTM C1424-04, "Standard Test Method for Monotonic Compressive Strength of Advanced Ceramics at Ambient Temperature".

ASTM E1461-13, "Standard Test Method for Thermal Diffusivity by the Flash Method".

ASTM E1933-14, "Standard Practice for Measuring and Compensating for Emissivity Using Infrared Imaging Radiometers".

Desired Deliverables

Phase I: In addition to a final report with supporting analysis, awardees shall deliver NASA material samples from the effort that can be utilized for independent verification of claimed improvements over SOA technologies.

Phase II: In addition to a final report with supporting analysis, awardees shall demonstrate functionality of components derived from the effort when integrated with operating thruster hardware. Partnering with electric propulsion developers may be required.

Expected TRL or TRL range at completion of the project: 2 to 6

Relevance / Science Traceability

Both NASA's Science Mission Directorate (SMD) and Human Exploration and Operations Mission Directorate (HEOMD) need spacecraft with demanding propulsive performance and greater flexibility for more ambitious missions requiring high duty cycles and extended operations under challenging environmental conditions. Planetary spacecraft need the ability to rendezvous with, orbit, and conduct in situ exploration of planets, moons, and other small bodies (i.e., comets, asteroids, near-Earth objects, etc.) in the solar system; furthermore, mission priorities are outlined in the decadal surveys for each of the SMD divisions (https://science.nasa.gov/about-us/science-strategy/decadal-surveys [28]). For HEOMD, higher-power electric propulsion is a key element (e.g., the Power and Propulsion Element of the Lunar Gateway) in supporting sustained human exploration of cis-lunar space.

This subtopic seeks innovations to meet future SMD and HEOMD propulsion requirements in electric propulsion systems related to such missions. The innovations would enable lower-cost electric propulsion systems for small spacecraft, Discovery-class missions, and low-power NEP (nuclear electric propulsion) missions while improving the reliability and robustness of higher-power electric propulsion systems to support human missions. The roadmap for such in-space propulsion technologies is covered under the 2015 NASA Technology Roadmap TA-2 (In-Space Propulsion Technologies).

Scope Title

Photovoltaic Energy Conversion

Scope Description

Photovoltaic cell and blanket technologies that lead to significant improvements in overall solar array performance by increasing photovoltaic cell efficiency greater than 30%, increasing array mass specific power greater than 300W/ kg, decreased stowed volume, reduced initial and recurring costs, long- term operation in radiation environments, high power arrays and a wide range of space environmental operating conditions are solicited.

Photovoltaic Energy Conversion: advances in, but not limited to, the following: (1) Photovoltaic cell and blanket technologies capable of low intensity, low-temperature operation applicable to outer planetary (low solar intensity) missions, (2) Photovoltaic cell, and blanket technologies that enhance and extend performance in lunar applications including orbital, surface and transfer, (3) Solar arrays to support Extreme Environments Solar Power type missions, including long-lived, radiation tolerant, cell and blanket technologies applicable to Jupiter missions, and (4) Lightweight solar array technologies applicable to science missions using solar electric propulsion.

Current missions being studied require solar arrays that provide 1 to 20 kilowatts of power at 1 AU, greater than 300 watts/kilogram specific power, operation in the range of 0.7 to 3 AU, low stowed volume, and the ability to provide operational array voltages up to 300 volts to enable direct drive electric propulsion systems for science missions.

References

Solar Power Technologies for Future Planetary Science Missions, found at: https://solarsystem.nasa.gov/resources/548/solar-power-technologies-for-future-planetary-science-missions/ [30]

Scope Title

Photovoltaic Energy Conversion

Scope Description

Photovoltaic cell and blanket technologies that lead to significant improvements in overall solar array performance by increasing photovoltaic cell efficiency greater than 30%, increasing array mass specific power greater than 300W/ kg, decreased stowed volume, reduced initial and recurring costs, long- term operation in radiation environments, high power arrays and a wide range of space environmental operating conditions are solicited.

Photovoltaic Energy Conversion: advances in, but not limited to, the following: (1) Photovoltaic cell and blanket technologies capable of low intensity, low-temperature operation applicable to outer planetary (low solar intensity) missions, (2)Photovoltaic cell, and blanket technologies that enhance and extend performance in lunar applications including orbital, surface and transfer, (3) Solar arrays to support Extreme Environments Solar Power type missions, including long-lived, radiation tolerant, cell and blanket technologies applicable to Jupiter missions, and (4) Lightweight solar array technologies applicable to science missions using solar electric propulsion.

Current missions being studied require solar arrays that provide 1 to 20 kilowatts of power at 1 AU, greater than 300 watts/kilogram specific power, operation in the range of 0.7 to 3 AU, low stowed volume, and the ability to provide operational array voltages up to 300 volts to enable direct drive electric propulsion systems for science missions.

References

Solar Power Technologies for Future Planetary Science Missions, found at:
https://solarsystem.nasa.gov/resources/548/solar-power-technologies-for-future-planetary-science-missions/ [30]

NASA outlines New Lunar Science, Human Exploration Missions, found at:
https://www.nasa.gov/feature/nasa-outlines-new-lunar-science-human-exploration-missions [31]

NASA Science Missions, found at:
https://science.nasa.gov/missions-page?field_division_tid=All&field_phase_tid=3951 [32]

Expected TRL or TRL range at completion of the project 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Research

Desired Deliverables Description

Phase I deliverables include detailed reports with proof- of- concept and key metrics of components tested and verified.
Phase II deliverables include detailed reports with relevant test data along with proof- of- concept hardware and components developed.

State of the Art and Critical Gaps

State of the Art photovoltaic array technology consists of high efficiency, multijunction cell technology on thick honeycomb panels. Lightweight arrays are just beginning to be developed. There are very limited demonstrated technology for High Intensity High Temperature (HIHT), Low Intensity Low Temperature (LILT), Solar Electric Propulsion (SEP) missions and Lunar orbital, surface or transfer applications.

Significant improvements in overall solar array performance are needed to address the current gaps between SOA (Sate of the Art) and many mission requirements for photovoltaic cell efficiency greater than 30%, array mass specific power greater than 300W/ kg, decreased stowed volume, reduced initial and recurring costs, long- term operation in radiation environments, high power arrays and a wide range of space, lunar, and planetary environmental operating conditions.

Relevance / Science Traceability

These technologies are relevant to any space science, earth science, planetary surface, or other science mission that requires affordable high-efficiency photovoltaic power production for orbiters, flyby craft, landers and rovers. Specific requirements can be found in the references listed above, but include many future Science Mission Directorate (SMD) missions. Specific requirements for orbiters and flybys to Outer planets include: LILT capability (>38% at 10 AU and <−140°C), radiation tolerance (6e15 1 MeV e-cm^2), high power (>50 kW at 1 AU), low mass (3× lower than SOP), low volume (3× lower than SOP), long life (>15 years), and high reliability.

These technologies are relevant and align to any Space Technology Mission Directorate (STMD) or Human Exploration and Operations Mission Directorate (HEOMD) mission that requires affordable high-efficiency photovoltaic power production.

NASA outlines New Lunar Science, Human Exploration Missions, found at:
https://www.nasa.gov/feature/nasa-outlines-new-lunar-science-human-exploration-missions [31]

NASA Science Missions, found at:
https://science.nasa.gov/missions-page?field_division_tid=All&field_phase_tid=3951 [32]

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

Scope Description

NASA is developing Dynamic Radioisotope Power Systems (DRPS) for unmanned robotic missions to the moon, and other solar system bodies of interest. This technology directly aligns with the Science Mission Directorate (SMD) strategic technology investment plan for space power and energy storage and could be infused into a highly efficient RPS for missions to dark, dusty, or distant destinations where solar power is not practical. Current work in dynamic radioisotope power systems is focused on novel Stirling, Brayton, or Rankine convertors that would be integrated with one or more 250 watt-thermal General Purpose Heat Source (GPHS) modules or 1 watt-thermal Light Weight Radioisotope heater Unit (RHU) to provide high thermal-to-electric efficiency, low mass, long life, and high reliability for planetary spacecraft, landers, and rovers. Heat is transferred from the radioisotope heat source assembly to the power convertor hot end using conductive or radiative coupling. Power convertor hot end temperatures would generally range from 300-500 °C for RHU applications and 500-800 °C for GPHS applications. Waste heat is removed from the cold end of the power convertor at temperatures ranging from 20-175 °C, depending on the application, using conductive coupling to radiator panels. The NASA projects target power systems able to produce a range of electrical power output levels based on the available form factors of space rated fuel sources. These include a very low range of 0.5-2.0 watt-electric that would utilize one or more RHU, a moderately range of 40-70 watt-electric that would utilize a single GPHS Step-2 module, and a high range of 100-500 watt-electric that would utilize multiple GPHS Step-2 modules. For these power ranges, one or more power convertors could be used to improve overall system reliability. The current solicitation is focused on innovations that enable efficient and robust power conversion systems. Areas of interest include:

1. Robust, efficient, highly reliable, and long-life thermal-to-electric power convertors that would be used to populate a generator of a prescribed electric power output range.
2. Electronic controllers applicable to Stirling, Brayton, or Rankine power convertors.   
3. Multi-Layered Metal Insulation (MLMI) for minimizing environmental heat losses and maximizing heat transfer from the radioisotope heat source assembly to the power convertor.
4. Advanced dynamic power conversion components and RPS integration components, including efficient alternators able to survive extended exposure to 200 °C, robust high-temperature tolerant Stirling regenerators, robust highly effective recuperators, integrated heat pipes, and radiators that improve system performance, and improving the margin, reliability, and fault tolerance for existing components.

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

References

Radioisotope Power Systems (RPS): https://rps.nasa.gov/about-rps/overview/ [34]

Oriti, Salvatore, "Dynamic Power Convertor Development for Radioisotope Power Systems at NASA Glenn Research Center," AIAA Propulsion and Energy (P&E) 2018, AIAA 2018-4498.

Wilson, Scott D., "NASA Low Power Stirling Convertor for Small Landers, Probes, and Rovers Operating in Darkness," AIAA P&E 2018, AIAA 2018-4499.

Wong, Wayne, "Advanced Stirling Convertor (ASC) Technology Maturation," AIAA P&E 2015, AIAA 2015-3806.

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Research

Desired Deliverables Description

The desired deliverables include prototype hardware that has demonstrated basic functionality in a laboratory environment and the appropriate research and analysis used to develop the hardware. Deliverables also include maturation options for flight designs.

State of the Art and Critical Gaps

Radioisotope Power Systems are critical for long duration NASA missions in dark, dusty, or harsh environments. Thermoelectric systems have been used on the very successful RPS flown in the past, but are limited in efficiency. Dynamic thermal energy conversion provides significantly higher efficiency and through proper engineering of the non-contact moving components, can eliminate wear mechanisms and provide long life. While high efficiency performance of dynamic power convertors has been proven, reliable and robust systems tolerant of off-nominal operation is needed. In addition to convertors appropriate for General Purpose Heat Source (GPHS) RPS, advances in much smaller and lower power dynamic power conversion systems are sought that can utilize Radioisotope Heater Units (RHU) for applications such as distributed sensor systems, small spacecraft, and other systems that take advantage of lower power electronics for the exploration of surface phenomenon on icy moons and other bodies of interest.  While the power convertor advances are essential, to develop reliable and robust systems for future flight, advances in convertor components as well as RPS integration components are also needed. These would include efficient alternators able to survive 200 C, robust high-temperature tolerant regenerators, robust high efficiency recuperators, heat pipes, radiators, and controllers applicable to Stirling flexure-bearing, Stirling gas-bearing, or Brayton convertors. Similar scope and content was previously included as part of the broader S3.01 subtopic last year. This nomination is for dynamic power conversion as a stand-alone subtopic under S3.

Relevance / Science Traceability

This technology directly aligns with the Science Mission Directorate - Planetary Science Division for space power and energy storage. Investments in more mature technologies through the Radioisotope Power System Program is ongoing. This SBIR subtopic scope provides a lower TRL technology pipeline for advances in this important power capability that improves performance, reliability, and robustness.

Scope Description

NASA's Planetary Science Division is working to implement a balanced portfolio within the available budget and based on a decadal survey that will continue to make exciting scientific discoveries about our solar system. This balanced suite of missions shows the need for low mass/volume energy storage that can effectively operate in extreme environments for future NASA Science Missions.

Future science missions will require advanced primary and secondary battery systems capable of operating at temperature extremes from -200° C for outer planet missions to 400 to 500° C for Venus missions, and a span of -230° C to +120° C for missions to the Lunar surface. Operational durations of 60 days for Titan and 14 days for the Moon are of interest. Advancements to battery energy storage capabilities that address operation at extreme temperatures combined with high specific energy and energy density (>200 Wh/kg and >200 Wh/l) are of interest in this solicitation.

In addition to batteries, other advanced energy storage/load leveling technologies designed to the above mission requirements, such as mechanical or magnetic energy storage devices, are of interest. These technologies have the potential to minimize the size and mass of future power systems.

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

References

• NASA Science:https://science.nasa.gov/ [36]
• Solar Electric Propulsion: h [37]ttps://www1.grc.nasa.gov/space/sep/ [37]

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype

Desired Deliverables Description

Research should be conducted to demonstrate technical feasibility during Phase I and show a path toward a Phase II, and when possible, deliver a demonstration unit for NASA testing at the completion of the Phase II contract. Phase II emphasis should be placed on developing and demonstrating the technology under relevant test conditions. Additionally, a path should be outlined that shows how the technology could be commercialized or further developed into science-worthy systems.

State of the Art and Critical Gaps

State-of the-art primary and rechargeable cells are limited in both capacity and temperature range.  Typical primary Li-SO₂ and Li-SOCl₂ operate within a max temperature range of -40 to 80 deg C but suffer from capacity loss, especially at low temperatures.  At -40 deg C, the cells will provide roughly half the capacity available at room temperature. Similarly, rechargeable Li-ion cells operate within a narrow temperature range of -20 to 40 C and also suffer from capacity loss at lower temperatures. The lower limit of temperature range of rechargeable cells can be extended through the use of low temperature electrolytes, but with limited rate capability and concerns over lithium plating on charge. There is currently a gap that exists for high temperature batteries, primary and rechargeable, that can operate at Venus atmospheric temperatures. This solicitation is aimed at the development of cells that can maintain performance at extreme temperatures so as to minimize or eliminate the need for strict thermal management of the batteries, which adds complexity and mass to the spacecraft.

Relevance / Science Traceability

These batteries are applicable over a broad range of science missions.  Low temperature batteries are needed for potential NASA decadal missions to Ocean Worlds (Europa, Enceladus, and Titan) and the Icy Giants (Neptune, Uranus). These batteries are also needed for science missions on the lunar surface. Low temperature batteries developed under this subtopic would enhance these missions and could be potentially enabling if the missions are mass or volume limited.  There is also significant interest in a Venus surface mission that will require primary and/or rechargeable batteries that can operate for 60+ days on the surface of Venus. A high temperature battery that can meet these requirements is enabling for this class of missions.

Scope Title

Kilowatt-Class Fission Energy Conversion

Scope Description

NASA is considering the use of kilowatt class Fission Power Systems for surface missions to the moon and Mars. This technology directly aligns with the Space Technology Mission Directorate (STMD) roadmap for space power and energy storage. Prior work in fission power systems had focused on a 1kWe ground demonstration, however, NASA desires to scale-up the system and components for a flight demo mission to the lunar surface, so component technologies that support a 10kWe-class fission power system are sought that address the following technical challenges:

• Robust, efficient, highly reliable, and long-life thermal-to-electric power conversion in the range of 1-10kWe. Stirling, Brayton, and thermoelectric convertors that can be coupled to Kilopower reactors are of interest.
• Freeze tolerant heat pipe radiators that can operate through lunar night (-173 ºC) and day (127 ºC) temperature swings. Heat pipes must start-up from lunar night temperature and begin transferring heat within several thermal cycles.
• Radiation shield materials selection, design, and fabrication for mixed neutron and gamma environments, with consideration for mass effectiveness, manufacturability, and cost.
• Radiation tolerant generator control electronics designed to withstand an induced radiation environment in addition to the ambient environment in space. These electronics can include: source control and generation, high voltage outputs with dynamic response needed to meet power quality standards, short term heating prior to startup, shunt control to manage excess power production, and source monitoring for power management. Target dose tolerance ranges for fission power system electronics are between 1E11 to 1E13 n/cm² total neutron fluence, and between 100 kRad (Si) and 1000kRad (Si) total ionizing gamma dose. Natural space environment should also be considered, with specific attention to Single Event Effect susceptibility.

The desired deliverables are primarily prototype hardware, research, and analysis to demonstrate concept feasibility and a TRL range of 3 to 5. The prototype hardware may include one (or more) of the following:

• Power convertor (hot-end temperature = 800 ºC, cold-end temperature = 100 to 200 ºC)
• Heat pipe radiator (for up to 30 kW heat rejection)
• Radiation shield (reduce radiation down to 1E11 to 1E13 n/cm² neutron fluence and 100 to 1000 kRad TID at minimum mass)
• Control electronics (capable of surviving the radiation environment that passes through the radiation shield)

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

References

Kilopower (https://www.nasa.gov/directorates/spacetech/kilopower [39]).

Gibson, M.A., et al., "The Kilopwer Reactor Using Stirling TechnologY (KRUSTY) Nuclear Ground Test Results and Lessons Learned," AIAA P&E 2018, AIAA-2018-4973.

Mason, Lee S., "A Comparison of Energy Conversion Technologies for Space Nuclear Power Systems," AIAA P&E 2018, AIAA-2018-4977.

Chaiken, M.F., et al., "Radiation Tolerance Testing of Electronics for Space Fission Power Systems," Nuclear and Emerging Technologies for Space 2018, Paper No. 24146.

Gibson, M.A., et al., "NASA's Kilopower Reactor Development and the Path to Higher Power Missions," 2017 IEEE Aerospace Conference, 4-11 March 2017, Big Sky, MT.

Mason, Lee S., et al., "A Small Fission Power System for NASA Planetary Science Missions," NASA/TM--2011-217099.

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Hardware, Analysis, and Research

Desired Deliverables Description

We are primarily looking for component and/or breadboard hardware to demonstrate concept feasibility in a lab or relevant environment. The appropriate research and analysis required to develop the hardware are also desired.

State of the Art and Critical Gaps

Kilowatt-class fission power generation is an enabling technology for lunar and Mars surface missions that require day and night power for long-duration surface operations, and may be the only viable power option to achieve a sustained human presence. The surface assets that could benefit from a continuous and reliable fission power supply include landers, rover recharge stations, science platforms, mining equipment, ISRU (In-Situ Resource Utilization) propellant production, and crew habitats. Compared to solar arrays with energy storage, nuclear fission offers considerable mass savings, greater simplicity of deployment, improved environmental tolerance, and superior growth potential for increasing power demands. Fission power is also one of very few technologies that can be used on either the moon or Mars with the same basic design. A first-use on the moon provides an excellent proving ground for future Mars systems, on which the crew will be highly dependent for their survival and return propellant. The technology is also extensible to outer planet science missions with power requirements that exceed the capacity of radioisotope generators, including nuclear electric propulsion spacecraft that could enable certain science missions that might otherwise be impossible.

Current work on fission power systems has focused on a 1kWe design using a highly enriched Uranium-Molybdenum reactor core with a Beryllium oxide reflector. Depleted uranium, tungsten, and lithium hydride provide shielding of gamma rays and neutrons to the power conversion system, control electronics, payload, and habitat. Heat is removed from the core at approximately 800° C using sodium heat pipes and delivered to the power conversion system. Waste heat is removed from the power conversion system at approximately 100 to 200° C using water heat pipes coupled to aluminum or composite radiator panels.

Reliable, robust, and long life power conversion is highly desirable in fission systems. There are currently not enough vendors or enough long duration reliability data for power conversion technologies under these operating conditions and environments. More work is needed in this area to expand the supplier base, and to increase the TRL of power conversion technology. The reactor core must be isolated from the Martian environment to prevent oxidation. However, simply canning the core may not be an option since increased distance between the core and reflector can have large negative effects on system mass. Canning the reflector and core together is the simplest option; however, the increased temperature of the reflector results in reduced reactivity and increased mass. Innovations are necessary to provide isolation while reducing the negative effect due to the neutronics.

Total Ionizing Dose (TID) effects, Displacement Damage Dose (DDD) effects, and Single Event Effect (SEE) transients are well studied for the standard space radiation environment composed of charged particles and electromagnetic radiation of either solar or galactic origin. Aerospace electronics vendors offer high reliability product lines that have been qualified using standard irradiation testing procedures. These procedures do not typically cover the neutron environment of a nuclear fission reactor. Further qualification in a reactor radiation environment is needed for components and systems that will be used in a space fission power system.

Relevance / Science Traceability

This technology directly aligns with the STMD roadmap for space power and energy storage. This technology could be infused into the Kilopower Project to enhance performance or reliability.

Scope Title

Innovative ways to transmit high power for lunar & Mars surface missions

Scope Description

The Global Exploration Roadmap (January 2018) and the Space Policy Directive (December 2017) detail NASA’s plans for future human-rated space missions. A major factor in this involves establishing bases on the lunar surface and eventually Mars. Surface power for bases is envisioned to be located remotely from the habitat modules and must be efficiently transferred over significant distances. The International Space Station (ISS) has the highest power (100kW), and largest space power distribution system with eight interleaved micro-grids providing power functions similar to a terrestrial power utility. Planetary bases will be similar to the ISS with expectations of multiple power sources, storage, science, and habitation modules, but at higher power levels and with longer distribution networks providing interconnection. In order to enable high power (>100kW) and longer distribution systems on the surface of the moon or Mars, NASA is in need of innovative technologies in the areas of lower mass/higher efficiency power electronic regulators, switchgear, cabling, connectors, wireless sensors, power beaming, power scavenging, and power management control. The technologies of interest would need to operate in extreme temperature environments, including lunar night, and could experience temperature changes from -153C to 123C for lunar applications, and -125C to 80C for Mars bases. In addition to temperature extremes, technologies would need to withstand (have minimal degradation from) lunar dust/regolith, Mars dust storms, and space radiation levels.

While this subtopic would directly address the lunar and Mars base initiatives, technologies developed could also benefit other NASA Mission Directorates including SMD (Science Mission Directorate) and ARMD (Aeronautics Research Mission Directorate). Specific projects which could find value in the technologies developed herein include Gateway, In-Situ Resource Utilization (ISRU), Advanced Modular Power Systems (AMPS), In-Space Electric Propulsion (ISP), planetary exploration, and Hybrid Gas Electric Propulsion. The power levels may be different, but the technology concepts could be similar, especially when dealing with temperature extremes and the need for electronics with higher power density and efficiency.

Specific technologies of interest would need to address the lunar or Mars environment, and include:

• Application of wide bandgap electronics in DC-DC isolating converters with wide temperature (-70ºC to 150ºC), high power density (>2 kW/kg), high efficiency (>96%) power electronics and associated drivers for voltage regulation.
• Low mass, highly conductive wires and terminations that provide reliable small gauges for long distance power transmission in the 1-10kW range, low mass insulation materials with increased dielectric breakdown strength and void reductions with 600 V or greater ratings, and low loss/low mass shielding.
• Power beaming concepts to enable highly efficient flexible/mobile power transfer in the 100-1,000W range, including the fusion of power/communication/navigation.

(See Z13.02 - Dust Tolerant Mechanismssubtopic to propose power connection/termination related technologies that are impervious to environmental dust and enable robotic deployment, such as robotically-enabled high voltage connectors and/or near-field wireless power transfer in the 1-10kW range.)

References

The Global Exploration Roadmap, January 2018: https://www.nasa.gov/sites/default/files/atoms/files/ger_2018_small_mobile.pdf [41]

Space Policy Directive, December 2017: https://www.nasa.gov/topics/moon-to-mars/overview [18]

Expected TRL or TRL range at completion of the project 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Research

Desired Deliverables Description

Typically, deliverables under Phase I proposals are geared towards a technology concept with associated analysis and design. A final report usually suffices in summarizing the work. Phase II hardware prototypes will have opportunities for infusion into NASA technology testbeds and commercial landers.

State of the Art and Critical Gaps

While high power terrestrial distribution systems exist, there is no equivalent to a lunar or planetary base. Unique challenges must be overcome in order to enable a realistic power architecture for these future applications, especially when dealing with the environmental extremes which will be encountered. The temperature swings will be a critical requirement on any technology developed, from power converters to cabling or power beaming concepts. In addition, proposals will have to consider lunar regolith and Mars dust storms.

Relevance / Science Traceability

This subtopic would directly address the lunar and Mars surface initiatives. There are potential infusion opportunities with SMD (Science Mission Directorate) Commercial Lander Payload Services and HEOMD (Human Exploration and Operations Mission Directorate) Flexible Lunar Exploration (FLEx) Landers. In addition, technologies developed could benefit other NASA missions including Gateway. The power levels may be different, but the technology concepts could be similar, especially when dealing with temperature extremes.

Scope Description

NASA’s directives for space exploration and habitation require high-performance, high-voltage transistors and diodes capable of operating without damage in the natural space radiation environment. Recently, significant progress has been made in the research community in understanding the mechanisms of heavy-ion radiation induced damage and catastrophic failure of wide bandgap power transistors and diodes. This subtopic seeks to facilitate movement of this understanding into the successful development of radiation-hardened high voltage transistors and rectifiers to meet NASA mission power needs reliably in the space environment. These needs include:

• High-voltage, high-power solutions: Technology Area (TA) 3.3.3, Power Management and Distribution (PMAD) Distribution and Transmission calls out the need for development of radiation-hardened, high-voltage, extreme- temperature components for power distribution systems. NASA has a core need for diodes and transistors that meet the following specifications:
  • Diodes: minimum 1200 V, 40 A, with fast recovery < 50 ns;
  • Transistors: minimum 600 V, 40 A, with < 24 mohm on-state drain-source resistance.
• High-voltage, low-power solutions: In support of TA 8.1 (Remote Sensing Instruments and Sensors), radiation-hardened, high-voltage transistors are needed for low-mass, low-leakage, high-efficiency applications such as LIDAR Q-switch drivers, mass spectrometers, and electrostatic analyzers. High-voltage, fast-recovery diodes are needed to enhance performance of a variety of heliophysics and planetary science instruments.
  • Transistors: minimum 1000 V, < 40 ns rise and fall times;
  • Diodes: 2 kV to 5 kV, < 50 ns recovery time.
• High-voltage, low- to medium-power solutions: In support of peak-power solar tracking systems for planetary spacecraft and small satellites, transistors and diodes are needed to increase buck converter efficiencies through faster switching speeds.
  • Transistors: minimum 600 V, < 50 ns rise and fall times, current ranging from low to > 20 A.

Successful proposal concepts should result in the fabrication of transistors and/or diodes that meet or exceed the above performance specifications without susceptibility to damage due to the heavy-ion space radiation environment (single-event effects resulting in permanent degradation or catastrophic failure). These diodes and/or transistors will form the basis of innovative, high-efficiency, low mass and volume systems and therefore must significantly improve upon the electrical performance available from existing heavy-ion radiation-tolerant devices. Proposals must state the initial state of the art for the proposed technology and justify the expected final performance metrics. Well-developed plans for validating the tolerance to heavy-ion radiation must be included, and the expected total ionizing dose tolerance should be indicated and justified. Target radiation performance levels will depend upon the device structure due to the interaction of the high electric field with the ionizing particle:

• For vertical-field power devices: No heavy-ion induced permanent destructive effects upon irradiation while in blocking configuration (in powered reverse-bias/off state) with ions having a silicon-equivalent surface incident Linear Energy Transfer (LET) of 40 MeV-cm²/mg and sufficient energy maintain a rising LET level throughout the epitaxial layer(s).
• For all other devices: No heavy-ion induced permanent destructive effects upon irradiation while in blocking configuration (in powered reverse-bias/off state) with ions having a silicon-equivalent surface-incident Linear Energy Transfer (LET) of 75 MeV-cm²/mg and sufficient energy to fully penetrate the active volume prior to the ions reaching their maximum LET value (Bragg peak).

Other innovative heavy-ion radiation-tolerant high-power, high-voltage discrete device technologies will be considered that offer significant electrical performance improvement over state-of-the art heavy-ion radiation-tolerant power devices.

References

The following is only a partial listing of relevant references:

1. S. Kuboyama, et al., "Thermal Runaway in SiC Schottky Barrier Diodes Caused by Heavy Ions," IEEE Transactions on Nuclear Science, vol. 66, pp. 1688-1693, 2019.
2. D. R. Ball, et al., “Ion-Induced Energy Pulse Mechanism for Single-Event Burnout in High-Voltage SiC Power MOSFETs and Junction Barrier Schottky Diodes,” IEEE Nuclear and Space Radiation Effects Conference, San Antonio, TX, July 2019.
3. J. McPherson, et al., "Mechanisms of Heavy Ion Induced Single Event Burnout in 4H-SiC Power MOSFETs," International Conference on Silicon Carbide and Related Materials (ICSCRM), Kyoto, Japan, to be presented, September, 2019.
4. C. Abbate, et al., "Gate Damages Induced in SiC Power MOSFETs during Heavy-Ion Irradiation--Part I," IEEE Transactions on Electron Devices, to be published, 2019. [see also Part II ]
5. J.-M. Lauenstein, “Getting SiC Power Devices Off the Ground: Design, Testing, and Overcoming Radiation Threats,” Microelectronics Reliability and Qualification Working (MRQW) Meeting, El Segundo, CA, February 2018. https://ntrs.nasa.gov/search.jsp?R=20180006113 [43]
6. E. Mizuta, et al., "Single-Event Damage Observed in GaN-on-Si HEMTs for Power Control Applications," IEEE Transactions on Nuclear Science, vol. 65, pp. 1956-1963, 2018.
7. M. Zerarka, et al., "TCAD Simulation of the Single Event Effects in Normally-OFF GaN Transistors after Heavy Ion Radiation," IEEE Transactions on Nuclear Science, vol. 64, pp. 2242-2249, 2017.
8. J. Kim, et al., "Radiation damage effects in Ga₂O₃ materials and devices," Journal of Materials Chemistry C, vol. 7, pp. 10-24, 2019.
9. S. J. Pearton, et al., "Perspective: Ga₂O₃ for ultra-high power rectifiers and MOSFETS," Journal of Applied Physics, vol. 124, p. 220901, 2018.

Expected TRL or TRL range at completion of the project: 5 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware

Desired Deliverables Description

Deliverables in Phase II shall include prototype and/or production-ready semiconductor devices (diodes and/or transistors), device electrical and radiation performance characterization (device electrical performance specifications and heavy-ion radiation test results and total dose radiation analyses).

State of the Art and Critical Gaps

A prior version of this subtopic, "High-Power, High-Voltage Electronics" was active in 2016-2017 and paused for two years to give time for funded proposals and a similar Early Stage Innovation topic designed to understand the radiation-induced failure mechanisms in wide bandgap semiconductors to mature. This pause has allowed these studies to mature and it is now time to re-open this subtopic to provide a means for applying the knowledge gained toward fabrication of radiation hardened power devices that are tailored to meet performance criteria of a number of NASA technology needs.

High voltage silicon power devices are limited in current ratings and have limited power efficiency and higher losses than do commercial Wide Bandgap (WBG) power devices. Efforts to space-qualify WBG power devices to take advantage of their tremendous performance advantages revealed they are very susceptible to damage from the heavy ion space radiation environment (galactic cosmic rays) that cannot be shielded against. Higher voltage devices are more susceptible to these effects; as a result, to date, there are space qualified GaN (Gallium Nitride) transistors now available but these are limited to 300 V. Recent radiation testing of 600 V and higher GaN transistors have shown failure susceptibility at about 50% of the rated voltage, or less. Silicon carbide power devices have undergone several generation advances commercially, improving their overall reliability, but catastrophically fail at less than 50% of their rated voltage. NASA has funded modeling and experimental efforts to understand the silicon carbide's susceptibility to heavy-ion radiation. Re-opening of this topic will provide a path for development and fabrication of hardened designs based upon this research, and encourage progress in other wide bandgap technologies such as higher voltage GaN, gallium oxide, and possibly diamond. 

Specific needs in STMD (Space Technology Mission Directorate) and SMD (Science Mission Directorate) areas have been identified for spacecraft PMAD and science instrument power applications and device performance requirements to meet these needs are included in this subtopic nomination. In all cases, there is no alternative solution that can provide the mass and power savings sought to enable game-changing capability. Current PPUs (Power Processing Unit's) and instrument power systems rely on older silicon technology with many stacked devices and efficiency penalties. In NASA's move to do more with less (smaller satellites), the technology of this subtopic nomination is truly enabling.

A phase I funded SBIR under the S4.04 Extreme Environments Technology, was awarded (https://sbir.nasa.gov/SBIR/abstracts/19/sbir/phase1/SBIR-19-1-S4.04-3611... [44]) in 2019 to develop low-defect gallium oxide (Ga₂O₃) based high-voltage power diodes grown on commercially available bulk Ga₂O₃ substrates via a thin-film deposition technique. The S4.04 Subtopic Manager serves as a participating subtopic manager on this Z1 subtopic to foster good leveraging and to avoid duplication of efforts. The S4.04 subtopic solicits development of technology for extreme temperatures and high total ionizing dose radiation primarily. 

Other non-NASA funded efforts include:

Vertical GaN diode development has been a focus of ARPA-E PNDIODE and (previous) SWITCHES programs. Diodes developed under the SWITCHES program were shown by Sandia National Lab to have good switching reliability, but another Italian team has found they may degrade under high current stress. Heavy-ion radiation susceptibility has not been assessed and is not expected to be robust without design alteration.

DoD (Department of Defense) has two funded Ga₂O₃ technology SBIRs that focus on development of manufacturing capabilities as opposed to device design itself.

Relevance / Science Traceability

Power transistors and diodes form the building blocks of numerous power circuits for spacecraft and science instrument applications. This subtopic therefore feeds a broad array of space technology hardware development activities by providing single-event effect (heavy ion) radiation-hardened state-of-the-art device technologies that achieve higher voltages with lower power consumption and greater efficiency than presently available.

TA 3.3.3, Power Management and Distribution (PMAD) Distribution and Transmission calls out the need for development of radiation-hardened, high-voltage, extreme-temperature components for power distribution systems. This subtopic will serve as a feeder to the subtopic Z1.05 - Lunar & Planetary Surface Power Management & Distribution" in which wide bandgap circuits for PMAD applications are solicited. The solicited developments in this subtopic will also feed systems development for Kilopower due to the savings in size/mass combined with radiation hardness. In addition, power distribution for lunar and Martian habitats will benefit from power circuits adopting this subtopic through significantly improved power efficiencies and radiation hardness.

TA 8.1, Remote Sensing Instruments and Sensors, radiation-hardened, high-voltage transistors are needed for low-mass, low-leakage, high-efficiency applications such as LIDAR Q-switch drivers, mass spectrometers, and electrostatic analyzers. These applications are aligned with science objectives including Earth Science LIDAR needs, Jovian moon exploration, and Saturn missions. Finally, mass spectrometers critical to planetary and asteroid research and in the search for life on other planets such as Mars require high voltage power systems and will thus benefit from mass and power savings from this subtopic's innovations.

Scope Title

Neuromorphic Capabilities

Scope Description

The Neuromorphic Processors for In-Space Autonomy and Cognition subtopic specifically focuses on advances in signal and data processing. Neuromorphic processing will enable NASA to meet growing demands for applying artificial intelligence and machine learning algorithms on-board a spacecraft to optimize and automate operations. This includes enabling cognitive systems to improve mission communication and data processing capabilities, enhance computing performance, and reduce memory requirements. Neuromorphic processors can enable a spacecraft to sense, adapt, act and learn from its experiences and from the unknown environment without necessitating involvement from a mission operations team. Additionally, this processing architecture shows promise for addressing the power requirements that traditional computing architectures now struggle to meet in space applications.

The goal of this program is to develop neuromorphic processing software, hardware, algorithms, architectures, simulators and techniques as enabling capability for autonomous space operations. Emerging memristor and other radiation-tolerant devices, which shows potential for addressing the need for energy efficient neuromorphic processors and improved signal processing capability, is of particular interest due to its resistance to the effects of radiation.

Additional areas of interest for research and/or technology development include: a) spiking algorithms that learn from the environment and improve operations, b) neuromorphic processing approaches to enhance data processing, computing performance, and memory conservation, and c) new brain-inspired chips and breakthroughs in machine understanding/intelligence. Novel memristor approaches which show promise for space applications are also sought.

This subtopic seeks innovations focusing on low size, weight and power (SWaP) applications suitable lunar orbital or surface operations, enabling efficient on-board processing at lunar distances. Focusing on SWaP-constrained platforms opens up the potential for applying neuromorphic processors in spacecraft or robotic control situations traditionally reserved for power-hungry general purpose processors. This technology will allow for increased speed, energy efficiency and higher performance for computing in unknown and un-characterized space environments including the Moon and Mars.

Phase I will emphasize research aspects for technical feasibility and show a path toward a Phase II proposal. Phase I deliverables include concept of operations of the research topic, simulations and preliminary results. Early development and delivery of prototype hardware/software is encouraged.

Phase II will emphasize hardware and/or software development with delivery of specific hardware and/or software products for NASA, targeting demonstration operations on a low-SWaP platform. Phase II deliverables include a working prototype of the proposed product and/or software, along with documentation and tools necessary for NASA to use the product and/or modify and use the software. In order to enable mission deployment, proposed prototypes should include a path, preferably demonstrated, for fault tolerance and mission tolerance.

References

Several reference papers that have been published at the Cognitive Communications for Aerospace Applications (CCAA) workshop are available at: http://ieee-ccaa.com [46].

Expected TRL or TRL range at completion of the project 4 to 6

Desired Deliverables of Phase II

Prototype, Hardware, Software

Desired Deliverables Description

Phase 2 deliverables should include hardware/software necessary to show how the advances made in the development can be applied to a cubesat, small sat, and rover flight demonstration.

State of the Art and Critical Gaps

The current State-of-the-Art (SOA) for in-space processing is the High Performance Spaceflight Computing (HPSC) processor being developed by Boeing for NASA GSFC. The HPSC, called the Chiplet, contains 8 general purpose processing cores in a dual quad-core configuration. Delivery is expected by December 2022. In a submission to the STMD Game Changing Development (GCD) program, the highest computational capability required by a typical space mission is 35-70 GFLOPS (million fast logical operations per second).

The current SOA does not address the capabilities required for artificial intelligence and machine-learning applications in the space environment. These applications require significant amounts of multiply and accumulate operations, in addition to a substantial amount of memory to store data and retain intermediate states in a neural network computation. Terrestrially, these operations require General-Purpose Graphics Processing Units (GP-GPUs), which are capable of teraflops (TFLOPS) each -- approximately 3 orders of magnitude above the anticipated capabilities of the HPSC.

Neuromorphic processing offers the potential to bridge this gap through a novel hardware approach. Existing research in the area shows neuromorphic processors to be up to 1000 times more energy efficient than GP-GPUs in artificial intelligence applications. Obviously the true performance depends on the application, but nevertheless the architecture has demonstrated characteristics that make it well-adapted to the space environment.

Relevance / Science Traceability

The Cognitive Communications Project, through the Human Exploration and Operations Mission Directorate (HEOMD) Space Communications and Navigation (SCaN) Program, is one potential customer of work from this subtopic area. Neuromorphic processors are a key enabler to the cognitive radio and system architecture envisioned by this project. As communications become more complex, cognition and automation will play a larger role to mitigate complexity and reduce operations costs. Machine learning will choose radio configurations, adjust for impairments and failures. Neuromorphic processors will address the power requirements that traditional computing architectures now struggle to meet and are of relevance to lunar return and Mars for autonomous operations, as well as of interest to HEOMD and SMD for in-situ avionics capabilities.

Scope TitleDevelopment, Design, and Implementation of Fault Management TechnologiesScope DescriptionNASA’s science program has well over 100 spacecraft in operation, formulation, or development, generating science data accessible to researchers everywhere. As science missions have increasingly complex goals, often on compressed timetables, and have more pressure to reduce operations costs, system autonomy must increase in response.Fault Management (FM) is a key component of system autonomy, serving to detect, interpret, and mitigate failures that threaten mission success. Robust FM must address the full range of hardware failures, but also must consider failure of sensors or the flow of sensor data, harmful or unexpected system interaction with the environment, and problems due to faults in software or incorrect control inputs -- including failure of autonomy components themselves.Despite a wealth of lessons learned from past missions, spacecraft failures are still not uncommon and reuse of FM approaches is very limited, illustrating deficiencies our approach to handling faults in all phases of the flight project lifecycle. While this subtopic addresses particular interest in on-board Fault Management capabilities (viz. on-board sensing approaches, computing, algorithms, and models to assess and maintain spacecraft health), the goal isto provide a system capability, and thus off-board components such as modeling techniques and tools, development environments, testbeds, and verification and validation (V&V) technologies are also relevant.  Specific algorithms and sensor technologies are in scope provided their impact is not limited to a particular subsystem, mission goal, or failure mechanism.Innovations in Fault Management can be grouped into the categories below.

• Fault Management Design Tools: System modeling and analysis significantly contributes to the quality of FM design, and may prove decisive in trades of new vs. traditional FM approaches. However, the difficulty in translating system design information into system models often impacts modeling and analysis accuracy. Examples of enabling techniques and tools are automated modeling systems, spacecraft modeling libraries, algorithm prototyping and test environments, sensor placement analyses, and system modeling that supports multiple autonomy functions including FM. System design should enable multi-disciplinary assessment of FM approaches, addressing performance metrics, standardization of data products and models, and analyses to reduce design costs and design escapes.
• Fault Management Visualization Tools: FM systems have impacts on hardware, software, and operations. The ability to visualize the full FM system behavior and the contribution of each component to protecting mission functions and assets is critical to assessing completeness of the approach, and to evaluate appropriateness of the FM design against mission needs. Fault trees and state transition diagrams are simple visualization products. Other examples of visualization could focus on margin management, probabilistic risk assessment, or FM impacts on scenario timelines.
• Fault Management Operations Approaches:  This category encompasses FM "in the loop," including algorithms, computing, state estimation / classification, machine learning, and model-based reasoning. Advanced FM approaches may reduce the need for spacecraft safing and reliance on mission operations through more accurate health assessment, early detection of problems, more effective discrimination and understanding of root causes, or automated recovery. Particularly desirable are technologies and approaches that enable new mission concepts with greater autonomy, minimizing or eliminating spacecraft safing in response to faults – for example, riding out failures gracefully, or autonomously recovering and restarting system behavior to complete science objectives that require timely execution. Future spacecraft must be able to make decisions about how to recover from failures or degraded capacity and continue the mission, and also to work cooperatively with mission operations to replan mission goals apace with changes in system capability.
• Fault Management Verification and Validation Tools: Along with difficulties in system engineering, the challenge of V&V’ing implementations of new FM technologies has been a significant barrier to infusion in flight projects. As complexity of spacecraft and systems increases, the testing required to verify and validate FM implementations can become prohibitively resource intensive without new approaches. Automated test case development, false positive/false negative test tools, model verification and validation tools, and test coverage risk assessments are examples of contributing technologies.
• Fault Management Design Architectures: FM capabilities may be implemented through numerous system, hardware, and software architecture solutions. The FM architecture trade space includes options such as embedding within the flight control software or deployment as independent onboard software; on-board versus ground-based capabilities; centralized or distributed FM functions; sensor suite implications; integration of multiple FM techniques; innovative software FM architectures implemented on flight processors or on Field Programmable Gate Arrays (FPGAs); and execution in real-time or off-line analysis post-operations. Alternative architecture choices such as model-based approaches could help control FM system complexity and cost and could offer solutions to transparency, verifiability, and completeness challenges.

Expected outcomes and objectives of this subtopic are to mature the practice of Fault Management, leading to better estimation and control of FM complexity and development costs, more flexible and effective FM designs, and accelerated infusion into future missions through advanced tools and techniques. Specific objectives include the following:

• Improve predictability of FM system complexity and estimates of development and operations costs
• Enable cost-effective FM design architectures and operations
• Determine completeness and appropriateness of FM designs and implementations
• Decrease the labor and time required to develop and test FM models and algorithms
• Improve visualization of the full FM design across hardware, software, and operations procedures
• Determine extent of testing required, completeness of verification planned, and residual risk resulting from incomplete coverage
• Increase data integrity between multi-discipline tools
• Standardize metrics and calculations across FM, SE, S&MA and operations disciplines
• Increase reliability of FM systems
• Overall, bound and improve costs and implementation risks of FM while improving capability, such that benefits demonstrably outweigh the risks, leading to mission infusion

ReferencesNASA's approach to Fault Management and the various needs are summarized in the NASA FM Handbook (https://www.nasa.gov/pdf/636372main_NASA-HDBK-1002_Draft.pdf [48]). Additional information is included in the talks presented at the 2012 FM Workshop (https://www.nasa.gov/offices/oce/documents/2012_fm_workshop.html [49], particularly https://www.nasa.gov/pdf/637595main_day_1-brian_muirhead.pdf [50]) Another resource is the NASA Technical Memorandum "Introduction to System Health Engineering and Management for Aerospace (ISHEM)" (https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20060003929.pdf [51]). This is greatly expanded on in the following publication: Johnson, S. (ed), System Health Management with Aerospace Applications, Wiley, 2011 (https://www.wiley.com/en-us/System+Health+Management%3A+with+Aerospace+Applications-p-9781119998730 [52])Fault Management Technologies are strongly associated with autonomous systems as a key component of situational awareness and system resilience.  A useful overview was presented at the 2018 Science Mission Directorate (SMD) Autonomy Workshop (https://science.nasa.gov/technology/2018-autonomy-workshop [53]), archiving a number of talks on mission challenges and design concepts.Expected TRL or TRL range at completion of the project: 3 to 4Desired Deliverables of Phase IIPrototype, Analysis, SoftwareDesired Deliverables DescriptionThe aim of the Phase I project should be to demonstrate the technical feasibility of the proposed innovation and thereby bring the innovation closer to commercialization. Note, however, the R&D undertaken in Phase I is intended to have high technical risk, and so it is expected that not all projects will achieve the desired technical outcomes.The required deliverable at the end of an SBIR Phase I contract is a report that summarizes the project’s technical accomplishments. As noted above, it is intended that proposed efforts conduct an initial proof of concept, after which successful efforts would be considered for follow-on funding by SMD missions as risk-reduction and infusion activities.  Research should be conducted to demonstrate technical feasibility and NASA relevance during Phase I and show a path toward a Phase II prototype demonstration.The Final Report should thoroughly document the innovation, its status at the end of the effort, and as much objective evaluation of its strengths and weaknesses as is practical. The report should include a description of the approach, foundational concepts and operating theory, mathematical basis, and requirements for application. Results should include strengths and weaknesses found, measured performance in tests where possible.Additional deliverables may significantly clarify the value and feasibility of the innovation. These deliverables should be planned to demonstrate retirement of development risk, increasing maturity, and targeted applications of particular interest. While the wide range of innovations precludes a specific list, some possible deliverables are listed below:

• For innovations that are algorithmic in nature, this could include development code or prototype applications, demonstrations of capability, and results of algorithm stress-testing.
• For innovations that are procedural in nature, this may include sample artifacts such as workflows, model prototypes and schema, functional diagrams, examples, or tutorial applications.
• Where a suitable test problem can be found, documentation of the test problem and a report on test results, illustrating the nature of the innovation in a quantifiable and reproducible way. Test reports should discuss maturation of the technology, implementation difficulties encountered and overcome, and results and interpretation.

State of the Art and Critical GapsMany recent Science Mission Directorate (SMD) missions have encountered major cost overruns and schedule slips due to difficulty in implementing, testing, and verifying FM functions. These overruns are invariably caused by a lack of understanding of FM functions at early stages in mission development, and by FM architectures that are not sufficiently transparent, verifiable, or flexible enough to provide needed isolation capability or coverage. In addition, a substantial fraction of SMD missions continue to experience failures with significant mission impact, highlighting the need for better FM understanding early in the design cycle, more comprehensive and more accurate FM techniques, and more operational flexibility in response to failures provided by better visibility into failures and system performance. Furthermore, SMD increasingly selects missions with significant operations challenges, setting expectations for FM to evolve into more capable, faster-reacting, and more reliable on-board systems.The SBIR program is an appropriate venue due to the following factors:

• Traditional FM design has plateaued, and new technology is needed to address emerging challenges. There is a clear need for collaboration and incorporation of research from outside the spaceflight community, as fielded FM technology is well behind the state of the art and failing to keep pace with desired performance and capability.
• The need for new FM approaches spans a wide range of missions, from improving operations for relatively simple orbiters to enabling entirely new concepts in challenging environments. Development of new FM technologies by SMD missions themselves is likely to produce point solutions with little opportunity for reuse and will be inefficient at best compared to a focused, disciplined research effort external to missions.
• SBIR level of effort is appropriately sized to perform intensive studies of new algorithms, new approaches, and new tools. The approach of this subtopic is to seek the right balance between sufficient reliability and cost appropriate to each mission type and associated risk posture. This is best achieved with small and targeted investigations, enabled by captured data and lessons learned from past or current missions, or through examination of knowledge capture and models of missions in formulation. Following this initial proof of concept, successful technology development efforts under this subtopic would be considered for follow-on funding by SMD missions as risk-reduction and infusion activities. Research should be conducted to demonstrate technical feasibility and NASA relevance during Phase I and show a path toward a Phase II prototype demonstration.

Relevance / Science TraceabilityFM technologies are applicable to all SMD missions, albeit with different emphases. Medium to large missions have very low tolerance for risk of mission failure, leading to a need for sophisticated and comprehensive fault management. Small missions, on the other hand, have a higher tolerance for risks to mission success but must be highly efficient, and are increasingly adopting autonomy and FM as a risk mitigation strategy.A few examples are provided below, although these may be generalized to a broad class of missions:Lunar Flashlight:  Enable very low-cost operations and high science return from a 6U cubesat through on-board error detection and mitigation, streamlining mission operations. Provide autonomous resilience to on-board errors and disturbances that interrupt or interfere with science observations.Europa Clipper: Provide on-board capability to detect and correct radiation-induced execution errors. Provide reliable reasoning capability to restart observations after interruptions without requiring ground in-the-loop. Provide MBSE tools to model and analyze FM capabilities in support of design trades, V&V of FM capabilities, and coordinated development with flight software.Rovers and Rotorcraft (Mars Sample Return, Dragonfly): Provide on-board capability for systems checkout, enabling lengthy drives/flights between Earth contacts and mobility after environmentally-induced anomalies (e.g., unexpected terrain interaction). Improve reliability of complex activities (e.g., navigation to features, drilling and sample capture, capsule pickup and remote launch).Search for Extrasolar Planets (Observation): Provide sufficient system reliability through on-board detection, reasoning, and response to enable long-period, stable observations. Provide on-board or on-ground analysis capabilities to predict system response and optimize observation schedule. Enable reliable operations while out of direct contact (e.g., deliberately occluded from Earth to reduce photon, thermal, and radio frequency background).

Scope Title

Enabling Technologies for Swarm of Space Vehicles

Scope Description

This subtopic is focused on developing and demonstrating technologies that enable cooperative operation of swarms of space vehicles in a dynamic environment. Primary interest is in technologies appropriate for low-cardinality (4-15 vehicle) swarms of small spacecraft, as well as planetary rovers and flyers (e.g., Mars helicopter). Large swarms and other platforms are of interest if well motivated in connection to NASA’s strategic plan and needs identified in decadal surveys.

The proposed technology should be motivated by a well-defined design reference mission presented in the proposal.

Possible areas of interest include but are not limited to:

• High precision relative localization and time synchronization in orbit and on planet surface.
• Coordinated task planning, operation, and execution with realistic communication limitations.
• Fast, real-time, coordinated motion planning in areas densely crowded by other agents and obstacles.
• Operations concepts and tools that provide situational awareness and commanding capability for a team of spacecraft or swarm of robots on another planet.
• Communication-less coordination by observing and estimating the actions of other agents in the multi-agent system.
• Cooperative manipulation and in-space construction
• Cooperative information gathering and estimation for exploration and inspection of a target object (large space structure or small asteroid).

Phase I awards will be expected to develop theoretical frameworks, algorithms, software simulation and demonstrate feasibility (TRL 2-3). Phase II awards will be expected to demonstrate capability on a hardware testbed (TRL 4-6).

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

References

[1] D. P. Scharf, F. Y. Hadaegh and S. R. Ploen, "A survey of spacecraft formation flying guidance and control (part 1): guidance," Proceedings of the 2003 American Control Conference, 2003. Denver, CO, USA, 2003, pp. 1733-1739.

[2] D. P. Scharf, F. Y. Hadaegh and S. R. Ploen, "A survey of spacecraft formation flying guidance and control. Part II: control," Proceedings of the 2004 American Control Conference, Boston, MA, USA, 2004, pp. 2976-2985 vol.4.

[3] Evan Ackerman, "PUFFER: JPL's Pop-Up Exploring Robot; This little robot can go where other robots fear to roll,“ https://spectrum.ieee.org/automaton/robotics/space-robots/puffer-jpl-popup-exploring-robot [55]

[4] "Precision Formation Flying,” https://scienceandtechnology.jpl.nasa.gov/precision-formation-flying [56]

[5] "Mars Helicopter to Fly on NASA’s Next Red Planet Rover Mission,"  https://www.nasa.gov/press-release/mars-helicopter-to-fly-on-nasa-s-next-red-planet-rover-mission/ [57]

[6] Miller, Duncan, Alvar Saenz-Otero, J. Wertz, Alan Chen, George Berkowski, Charles F. Brodel, S. Carlson, Dana Carpenter, S. Chen, Shiliang Cheng, David Feller, Spence Jackson, B. Pitts, Francisco Pérez, J. Szuminski and S. Sell. "SPHERES: A Testbed for Long Duration Satellite Formation Flying In MicroGravity Conditions." Proceedings of the AAS/AIAA Space Flight Mechanics Meeting, AAS 00-110, Clearwater, FL, Jan. 2000.

[7] S. Bandyopadhyay, R. Foust, G. P. Subramanian, S.-J. Chung, and F. Y. Hadaegh, "Review of Formation Flying and Constellation Missions Using Nanosatellites," Journal of Spacecraft and Rockets, vol. 53, no. 3, 2016, pp. 567-578.

[8] S. Kidder, J. Kankiewicz, and T. Vonder Haar. "The A-Train: How Formation Flying is Transforming Remote Sensing," https://atrain.nasa.gov/publications.php [58]

[9] T. Huntsberger, A. Trebi-Ollennu, H. Aghazarian, P. Schenker, P. Pirjanian, and H. Nayar. "Distributed Control of Multi-Robot Systems Engaged in Tightly Coupled Tasks," Autonomous Robots 17, 79–92, 2004.

[10] Space Studies Board, "Achieving Science with CubeSats: Thinking Inside the Box," National Academies of Sciences, Engineering, and Medicine, 2016. http://sites.nationalacademies.org/SSB/CompletedProjects/SSB_160539 [59]

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Software, Hardware, Research

Desired Deliverables Description

• Algorithms and research results clearly depicting metrics and performance of the developed technology in comparison to state of the art (SOA).
• Software implementation of the developed solution along with simulation platform.
• Prototype of the sensor or similar if proposal is to develop such subsystem.

State of the Art and Critical Gaps

Technologies developed under this subtopic enable and are critical for multi-robot missions (rovers and flying vehicles such as Mars helicopter) for collaborative planetary exploration, e.g., a team of small pop-up rovers (PUFFERS) that can collaboratively create a mesh network and explore high risk and hard to reach areas such as lava tubes, etc.

These technologies also enable successful formation flying spacecraft for multi-spacecraft synthetic aperture radar and interferometry (distributed space telescope) purposes, a team of smallsats forming a convoy which the lead triggers detailed measurements on the following spacecraft of a phenomena identified by the lead, or a team of smallsats collaboratively manipulating a defunct spacecraft or small asteroid.

Relevance / Science Traceability

Subtopic technology directly supports NASA Space Technology Roadmap TA4 (4.5.4 Multi-Agent Coordination, 4.2.7 Collaborative Mobility, 4.3.5 Collaborative Manipulation) and Strategic Space Technology Investment Plan (Robotic and Autonomous Systems: Relative GNC and Supervisory control of an S/C team), and is relevant to the following concepts:

• Multi-robot follow-on to the Mars 2020 and Mars Helicopter programs are likely to necessitate close collaboration among flying robots as advance scouts and rovers.
• Pop-Up Flat-Folding Explorer Robots (PUFFERs) are being developed at Jet Propulsion Laboratory (JPL) and promise a low-cost swarm of networked robots that can collaboratively explore lava-tubes and other hard to reach areas on planet surfaces.
• A convoy of spacecraft is being considered, in which the lead spacecraft triggers detailed measurement of a very dynamic event by the following spacecraft.

Multiple concepts for distributed space telescopes and distributed synthetic apertures are proposed that rely heavily on coordination and control technologies developed under this subtopic.

Scope Title

Artificial Intelligence for the Lunar Orbital Platform-Gateway

Scope Description

The Gateway is a planned lunar-orbit spacecraft that will have a power and propulsion system, a small habitat for the crew, a docking capability, an airlock and logistics modules. The Gateway is expected to serve as an intermediate way station between the Orion crew capsule and lunar landers as well as a platform for both crewed and un-crewed experiments. The Gateway is also intended to test technologies and operational procedures for suitability on long-duration space missions such as a mission to Mars. As such, it will require new technologies such as autonomous systems to run scientific experiments onboard, including biological experiments; perform system health management, including caution and warning; autonomous data management and other functions. In contrast to the International Space Station, Gateway is much more representative of lunar and deep-space missions---for example, the radiation environment.

This subtopic solicits autonomy, artificial intelligence and machine learning technologies to manage and operate engineered systems to facilitate long-duration space missions, with the goal of testing proposed technologies on Gateway. The current concept of operations for Gateway anticipates un-crewed (dormant) periods of up to nine months. Technologies need to be capable of or enable long-term, mostly unsupervised, autonomous operation. While crew are present, technologies need to augment the crew’s abilities and allow more autonomy from Earth-based Mission Control.  Additionally, the technologies may need to allow for coordination with the Orion crew capsule, lunar landers, Earth and their various systems and subsystems.

Examples of needs include but are not limited to:

1. Autonomous operations and tending of science payloads including environmental monitoring and support for live biological samples, and in-situ automated analysis of science experiments.
2. Prioritizing data for transmission from the Gateway. Given communications limitations, it may be necessary to determine what data can be stored for transmission when greater bandwidth is available, and what data can be eliminated as it will turn out to be useless, based on criteria relevant to the conduct of science and/or maintenance of the physical assets. Alternatively, it may be useful to adaptively compress data for transmission from the Gateway, which could include scientific experiment data and status, voice communications, scientific experiment data and status, and/or systems health management data.
3. Autonomous operations and health management of the Gateway. When Gateway is unoccupied, unexpected events or faults may require immediate autonomous detection and response, demonstrating this capability in the absence of support from Mission Control (which is enabling for future Mars missions and time-critical responses in lunar environment as well). Efforts to develop smart habitats will allow long-term human presence on the moon and Mars, such as the Space Technology Research Institutes (https://www.nasa.gov/press-release/nasa-selects-two-new-space-tech-research-institutes-for-smart-habitats [61]) are relevant.

References

Basic Moon to Mars Background: https://www.nasa.gov/topics/moon-to-mars/lunar-outpost [62]

Basic Gateway Background: https://www.nasa.gov/topics/moon-to-mars/lunar-gateway [63]

Crusan, J. C.; Smith, R. M.; Craig, D. A.; Caram, J. M.; Guidi, J.; Gates, M.; Krezel, J. M.; and Herrmann, N. 2018. Deep Space Gateway concept: Extending human presence into cislunar space. In Proceedings of the IEEE Aerospace Conference.

Autonomous Biological Systems (ABS) Experiments https://www.jstage.jst.go.jp/article/bss/12/4/12_4_363/_pdf/-char/en [64]

Deep Space Gateway Science Opportunities https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20180001581.pdf [65]

Conducting Autonomous Experiments in Space https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20180004314.pdf [66]

Expected TRL or TRL range at completion of the project: 2 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Software, Hardware, Research

Desired Deliverables Description

The deliverables range from research results to prototypes demonstrating various ways that autonomy and artificial intelligence (e.g., automated reasoning, machine learning, and discrete control) can be applied to aspects of Gateway operations and health management individually and/or jointly. As one example, for autonomous biological science experiments, the prototype could include hardware to host live samples for a minimum of 30 days that provide monitoring and environmental maintenance, as well as software to autonomously remedy issues with live science experiments. As another example, software that monitors the gateway habitat while un-crewed, automatically notifies of any off-nominal conditions, and then, when crew arrive, transitions the gateway from quiescent status to a status capable of providing the crew with life support. As another example, machine learning from the data stream of Gateway sensors to determine anomalous vs. nominal conditions and prioritize and compress data communications to Earth.

Phase 1 deliverables minimally include a detailed concept for autonomy technology to support Gateway operations such as experiments. Prototypes of software and/or hardware are strongly encouraged. Phase 2 deliverables will be full technology prototypes that could be subsequently matured for deployment on Gateway. Coordination with related efforts, such as the Space Technology Research Institutes (https://www.nasa.gov/press-release/nasa-selects-two-new-space-tech-research-institutes-for-smart-habitats [61]) is expected to eliminate redundancy of effort and allow appropriate interactions between Gateway and smart habitats.

State of the Art and Critical Gaps

The current state-of-the-art in human spaceflight allows for autonomous operations of systems of relatively limited scope, involving only a fixed level of autonomy (e.g., amount of human involvement needed), and learning at most one type of function (e.g., navigation). The Gateway will require all operations and health management to be autonomous at different levels (almost fully autonomous when no astronauts are on board vs. limited autonomy when astronauts are present), will require the autonomy to learn from human operations, and will require autonomy across all functions. The autonomy will also need to adapt to new missions and new technologies.

As NASA continues to expand with the eventual goal of Mars missions, the need for autonomous tending of science payloads will grow substantially. In order to address the primary health concerns for crew on these missions, it is necessary to conduct science in the most relevant environment. Acquisition of this type of data will be challenging while the gateway and Artemis missions are being performed due to limited crewed missions and limited crew time.

Relevance / Science Traceability

Gateway and other space station-like assets in the future will need:  The ability to learn autonomous operations from human operations which will be critical as the assets are expected to operate increasingly autonomously due to increasing duration space missions such as missions to Mars.

Scope Title

Robotic Mobility, Manipulation and Sampling

Scope Description

Technologies for robotic mobility, manipulation, and sampling are needed to enable access to sites of interest and acquisition and handling of samples for in-situ analysis or return to Earth from planets and small planetary bodies. The Moon and planetary moons with liquid oceans are of particular interest, as well as Mars, comets, and asteroids.

Mobility technologies are needed to enable access to steep and rough terrain for planetary bodies where gravity dominates, such as Earth’s moon and Mars. Wheeled, legged, and aerial solutions are of interest. Wheel concepts with good tractive performance in loose sand while being robust to harsh rocky terrain are of interest. Technologies to enable mobility on small bodies and access to liquid below the surface (e.g., in conduits or deep oceans) are desired, as well as the associated sampling technologies. Manipulation technologies are needed to deploy sampling tools to the surface, transfer samples to in-situ instruments and sample storage containers, and hermetically seal sample chambers. Sample acquisition tools are needed to acquire samples on planetary and small bodies through soft and hard materials, including ice. Minimization of mass and ability to work reliably in the harsh mission environment are important characteristics for the tools. Finally, design for planetary protection and contamination control is important for sample acquisition and handling systems.

Component technologies for low-mass and low-power systems tolerant to the in-situ environment, e.g. temperature, radiation, and dust, are of particular interest. Technical feasibility should be demonstrated during Phase I and a full capability unit of at least TRL 4 should be delivered in Phase II. Proposals should show an understanding of relevant science needs and engineering constraints and present a feasible plan to fully develop a technology and infuse it into a NASA program. Specific areas of interest include the following:

• Surface mobility and sampling systems for planets, small bodies, and moons
• Near subsurface sampling tools such as icy surface drills to 30 cm depth deployed from a manipulator
• Subsurface ocean access such as via a deep drill system
• Sample handling technologies that minimize cross contamination and preserve mechanical integrity of samples
• Pneumatic sample transfer systems and particle flow measurement sensors
• Low mass/power vision systems and processing capabilities that enable fast surface traverse
• Active lighting stereo systems for landers and rovers
• Electro-mechanical connectors enabling tool change-out in dirty environments
• Tethers and tether play-out and retrieval systems
• Miniaturized flight motor controllers
• Cryogenic operation actuators
• Robotic arms for low gravity environments

Proposers should also note a related subtopic exists that is focused solely on lunar robotic missions (see Z5.05, Lunar Rover Technologies for In-Situ Resource Utilization and Exploration), under the Space Technology Mission Directorate). With NASA's present emphasis on lunar exploration, Z5.05 is provided to help develop innovative lunar rover technologies to support in-situ resource utilization activities and for developing ideas, subsystem components, software tools, and prototypes that contribute to more capable and/or lower cost lunar robots. In particular, cryogenic or cryo-capable actuators that are specifically for lunar rover applications should be directed towards Z5.05.

References

Mars Exploration/Programs & Missions: https://mars.nasa.gov/programmissions/ [68]

Solar System Exploration: https://solarsystem.nasa.gov/ [69]

Ocean Worlds website: https://www.nasa.gov/specials/ocean-worlds/ [70]

Ocean Worlds article: https://science.nasa.gov/news-articles/ocean-worlds [71]

Expected TRL or TRL range at completion of the project: 2 to 4

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Hardware and software for component robotic systems.

State of the Art and Critical Gaps

Scoops, powder drills, and rock core drills and their corresponding handling systems have been developed for sample acquisition on Mars and asteroids. Non-flight systems have been developed for sampling on comets, Venus, and Earth's moon. However, these have not been incorporated in a robotic mission, and the lack of a sufficient solution or technology readiness level is in some cases the reason a mission has not yet been possible. Exploration of icy ocean worlds is in the concept phase and associated sampling and sample handling systems do not exist.

Relevance / Science Traceability

The subtopic supports multiple programs within Science Mission Directorate (SMD). The Mars program has had infusion of technologies such as a force-torque sensor in the Mars 2020 mission. Recent awards would support the Ocean Worlds program: surface and deep drills for Europa. Products from this subtopic have been proposed for New Frontiers program missions. With renewed interest in return to Earth's moon, the mobility and sampling technologies could support future robotic missions to the moon.

Scope Title

Develop Information Technologies to Improve Space Robots.

Scope Description

Extensive and pervasive use of robots can significantly enhance space exploration and space science, particularly for missions that are progressively longer, complex, and distant. The performance of these robots is directly linked to the quality and capability of the information technologies used to build and operate them. With few exceptions, however, current information technology used for state-of-the-art robotics is designed only to meet the needs of terrestrial applications and environments.

The objective of this subtopic, therefore, is to encourage the adaptation, maturation, and retargeting of terrestrial information technologies for space robotics. Proposals should address at least one of the following research areas:

1. Perception systems for autonomous robot operations in man-made environments (inside spacecraft or habitats) and unstructured, natural environments (Earth, Moon, Mars). The primary objective is to significantly increase the performance and robustness of perception capabilities such as object/hazard identification, localization, mapping, etc. through new avionics (including Commercial Off-The-Shelf [COTS] processors for use in space), sensors and/or software. Proposals for small size, weight, and power (SWAP) systems or technology that can operate on existing rad-hard processors are particularly encouraged.
2. Robot user interfaces that facilitate distributed human-robot teams, geospatial data visualization, summarization and notification, performance monitoring, etc. The primary objective is to enable more effective and efficient interaction with robots remotely operated with discrete commands or supervisory control. User interface technology that helps optimize operator workload or improve human understanding of autonomous robot actions are particularly encouraged. Note: proposals to develop user interfaces for direct teleoperation (manual control), augmented/virtual reality, or telepresence are not solicited and will be considered non-responsive.
3. Robot Operating System v2 (ROS 2) for space robots. The primary objective is reduce the risk of deploying, integrating, and verifying and validating the open-source ROS 2 for future space missions. Proposals that develop software technology that can facilitate integration of ROS 2 with common flight software (Core Flight Software, Integrated Test and Operations System [ITOS], etc.) and standards (Consultative Committee for Space Data Systems [CCSDS], etc.), methods to improve the suitability of ROS 2 for use with current flight computing, or tools / process to make ROS 2 (or a subset) ready for near-term flight missions are particularly encouraged.

Proposals are particularly encouraged to develop technologies applicable to robots of similar archetypes and capabilities to current NASA robots, such as Astrobee, Curiosity, or Robonaut 2.

References

https://www.nasa.gov/astrobee [73]

https://robonaut.jsc.nasa.gov [74]

J. Crusan, et al. 2018. "Deep space gateway concept: Extending human presence into cislunar space", In Proceedings of IEEE Aerospace Conference, Big Sky, MT

M. Bualat, et al. 2018. "Astrobee: A new tool for ISS operations". In Proceedings of AIAA SpaceOps, Marseille, France.

T. Fong, et al. 2013. "Smart SPHERES: a telerobotic free-flyer for intravehicular activities in space". In Proceedings of AIAA Space 2013, San Diego, CA.

M. Diftler, et al. 2011. "Robonaut 2 - The first humanoid robot in space". In Proceedings of IEEE International Conference on Robotics and Automation, Shanghai, China.

Expected TRL or TRL range at completion of the project: 4 to 6

Desired Deliverables (Phase I)

Proposers should develop technologies that can be demonstrated with, or integrated to existing NASA research robots or projects to maximize relevance and infusion potential.

1. Identify scenarios, use cases, and requirements.
2. Define specifications.
3. Develop preliminary design.

Desired Deliverables (Phase II)

1. Develop prototypes (hardware and/or software).
2. Demonstrate and evaluate prototypes in real-world settings.
3. Deliver prototypes to NASA.

State of the Art and Critical Gaps

Future exploration and science missions will require robots to operate in more difficult environments, carry out more complex tasks, and handle more dynamic and varying operational constraints than the current state of the art, which relies on low-performance, rad-hard computing and execution of pre-planned command sequences. To achieve these capabilities, numerous new information technologies need to be developed, including high performance space computing, autonomy algorithms, and advanced robot software systems (on-board and off-board).

For example, in contrast to the International Space Station, which is continuously manned, the Gateway is expected to only be intermittently occupied – perhaps as little as 8% of the time. Consequently, there is a significant need for the facility to be robotically tended, in order to maintain and repair systems in the absence of human crew. These robots will perform a wide range of caretaking work including inspection, monitoring, routine maintenance, and contingency handling. To do this, significant advances will need to be made in autonomous perception and robot user interfaces, particularly to handle mission-critical and safety-critical operations.

As another example, a mission to explore and map interior oceans beneath the ice on Europa will require a robot to penetrate an unknown thickness of ice, autonomously carry out a complex set of activities, and navigate back to the surface in order to transmit data back to Earth. The robot will need to perform these tasks with minimal human involvement and while operating in an extremely harsh and dynamic environment. To do this, significant advances will need to be made in autonomous perception and on-board software, particularly to compensate for poor (bandwidth-limited, high-latency, intermittent) communications and the need for high performance autonomy.

Relevance / Science Traceability

The development of information technology for intelligent and adaptive space robotics is well aligned with NASA goals for robotics. In particular, this development directly addresses multiple areas (TA4, TA7, TA11) of the 2015 NASA technology roadmap. Additionally, this development is directly aligned with multiple portions of the NASA Autonomous Systems SCLT (Systems Capability Leadership Team) technology taxonomy. Moreover, this development directly addresses a core technology area (robotics and autonomous systems) of the NASA Strategic Space Technology Investment Plan. Finally, the technology is directly aligned with the needs of numerous projects and programs in Aeronautics Research Mission Directorate (ARMD), Human Exploration and Operations Mission Directorate (HEOMD), Science Mission Directorate (SMD), and Space Technology Mission Directorate (STMD).

• ARMD: The technology can be applied to a broad range of unmanned aerial systems (UAS), including both small-scale drones and Predator / Global Hawk type systems. The technology can also be potentially infused into other flight systems that include autonomous capabilities, such as Urban Air Mobility vehicles.
• HEOMD: The technology is directly relevant to "caretaker" robots, which are needed to monitor and maintain human spacecraft (such as the Gateway) during dormant/uncrewed periods. The technology can also be used by precursor lunar robots to perform required exploration work prior to the arrival of humans on the Moon.
• SMD: The technology is required for future missions in Earth Science, Heliophysics, and Planetary Science (including the Moon, icy moons and ocean worlds) that require higher performance and autonomy than currently possible. In particular, missions that must operate in dynamic environments, or measure varying phenomena, will require the technology developed by this subtopic.
• STMD: The technology is directly applicable to numerous current mid-TRL (Game Changing Development program) and high-TRL (Technology Demonstration Mission program) Research and Development (R&D) activities, including Astrobee, In-space Robotic Manufacturing and Assembly, etc.

Scope Title

Improve the capability or performance of intravehicular activity robots

Scope Description

To support human exploration beyond Earth orbit, NASA is preparing to develop the "Gateway", which will be an orbiting facility near the Moon. This facility would serve as a starting point for missions to cis-lunar space and beyond. This facility could enable assembly and servicing of telescopes and deep-space exploration vehicles. This facility could also be used as a platform for astrophysics, Earth observation, heliophysics, and lunar science.

In contrast to the ISS (International Space Station), which is continuously manned, the Gateway is expected to only be intermittently occupied by humans – perhaps only 1 month per year. Consequently, there is a significant need for the Gateway to have autonomous capabilities for performing payload operations and spacecraft caretaking, particularly when astronauts are not present. Intra-Vehicular Activity (IVA) robots can potentially perform a wide variety of tasks including systems inspection, monitoring, diagnostics and repair, logistics and consumables stowage, exploration capability testing, aggregation of robotically returned destination surface samples, and science measurements and ops.

The objective of this subtopic, therefore, is to develop technologies that can improve the capability or performance of IVA robots to perform payload operations and spacecraft caretaking. Proposals are specifically sought to create technologies that can be integrated and tested with the NASA Astrobee or Robonaut 2 robots in the following areas: (1) Sensors and perception systems for interior environment monitoring, inspection, modeling and navigation; (2) Robotic tools for manipulating logistics and stowage or performing maintenance, housekeeping or emergency management operations (e.g. fire detection & suppression in multiple constrained locations or cleaning lunar dust out of HEPA (High-Efficiency Particulate Air) filters; and (3) Operational subsystems that enable extended robot operations (power systems, efficient propulsion, etc.), increase robot autonomy (planning, scheduling, and task execution), or improve human-robot teaming (software architecture, remote operations methods, etc.).

References

What is Astrobee? - https://www.nasa.gov/astrobee [73]

What is a Robonaut? - https://www.nasa.gov/robonaut2 [76]

J. Crusan, et al. 2018. "Deep space gateway concept: Extending human presence into cislunar space", In Proceedings of IEEE Aerospace Conference, Big Sky, MT

M. Bualat, et al. 2018. "Astrobee: A new tool for ISS operations". In Proceedings of AIAA SpaceOps, Marseille, France.

T. Fong, et al. 2013. "Smart SPHERES: a telerobotic free-flyer for intravehicular activities in space". In Proceedings of AIAA Space 2013, San Diego, CA.

M. Diftler, et al. 2011. "Robonaut 2 - The first humanoid robot in space". In Proceedings of IEEE International Conference on Robotics and Automation, Shanghai, China.

M. Deans, et al. 2019. "Integrated System for Autonomous and Adaptive Caretaking (ISAAC)". Presentation, Gateway Intra-Vehicular Robotics Working Group Face to Face, Houston, TX; NASA Technical Reports Server [https://ntrs.nasa.gov/search.jsp?R=20190029054] [77]

Expected TRL or TRL range at completion of the project: 4 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Prototype components or subsystems. Proposals must describe how the technology will make a significant improvement over the current state of the art, rather than just an incremental enhancement, for a specific IVA robot application.

State of the Art and Critical Gaps

The technology developed by this subtopic would both enable and enhance the Astrobee free-flying robot and Robonaut 2 humanoid robot, which are the SOA for IVA robots. SBIR technology would improve the capability and performance of these robots to routinely and robustly perform IVA tasks, particularly internal spacecraft payload operations and logistics. New technology created by 2020 SBIR awards can be tested with these robots in ground testbeds at ARC and JSC during the SBIR period of performance. On-orbit testing on ISS may be possible during Phase 2 and beyond (Phase 2-E, 2-X, 3, etc.).

The technology developed by this subtopic would also fill technical gaps identified by the proposed GCD (Game Changing Development) "Integrated System for Autonomous and Adaptive Caretaking" (ISAAC) project, which will mature autonomy technology to support the caretaking of human exploration spacecraft. In particular, the SBIR technology would help provide autonomy and robotic capabilities that are required for in-flight maintenance (both preventive and corrective) of Gateway during extended periods when crew are not present.

Relevance / Science Traceability

This subtopic is directly relevant to the following STMD (Space Technology Mission Directorate) investments:

• Astrobee free-flying robot – GCD
• Integrated System for Autonomous and Adaptive Caretaking (ISAAC) – GCD
• Deep Space Smart Habitats – Space Technology Research Institutes (STRI)

This subtopic is directly relevant to the following HEOMD (Human Exploration and Operations Mission Directorate) investments:

• SPHERES/Astrobee facility – ISS
• Robonaut 2 humanoid robot – ISS
• Gateway program – Advanced Exploration Systems (AES)
• Logistics Reduction project – AES

Autonomous Systems Operations project – AES

Scope Title

Enabling Rover Technologies for Lunar Missions

Scope Description

The objective of this subtopic is to innovate lunar rover technologies that will enable In-Situ Resource Utilization (ISRU) and exploration missions. In particular, this subtopic will develop ideas, subsystems components, software tools, and prototypes that contribute to more capable and/or lower-cost lunar robots.

A potential lunar ISRU application is the prospecting, characterization, and collection of volatiles that could be processed to produce oxygen, fuel, etc. Recent remote sensing measurements, modeling, and data from LCROSS (Lunar Crater Observation and Sensing Satellite) indicates that there may be an abundance of volatiles (e.g., hydrogen) near the lunar poles. However, the distribution of the volatiles at and under the surface is unknown. The Lunar Rover Technologies for In-situ Resource Utilization and Exploration subtopic seeks new robotic technology that will enable rover technologies for lunar missions to support ISRU activities. This does not include new ISRU technology (which is solicited by subtopics T2.05 - Advanced Concepts for Lunar and Martian Propellant Production, Storage, Transfer, and Usage for the STTR solicitation and S4.02 - Robotic Mobility, Manipulation and Sampling for the SBIR solicitation).

The expected environment at the lunar poles involves all the challenges observed during the Apollo mission (thermal extremes, vacuum, radiation, abrasive dust, electrostatic dust) plus the addition of low sun angles, potentially less consolidated regolith, and permanently shadowed regions with temperatures as low as 40K. This subtopic seeks new technology to address these challenges.

Phase I success involves technical feasibility demonstration through analysis, prototyping, proof-of-concept, or testing. Phase II success will advance TRL to a level of 4-5. Of specific interest are:

• Mobility architectures, including novel mobility mechanisms and lunar dust tolerant mechanisms.
• Cryo-capable actuators capable of operating at extremely cold temperatures (in environments as cold as -230C).  Preferably solutions will not include heaters as they significantly increase the power draw for normal operations during the lunar day.  Novel materials capable of maintaining metallurgical properties at cryogenic temperatures will be considered.  Also desired are cryo actuators featuring dust tolerances and the ability to operate at high temperatures as well (approaching 150C).
• Magnetic gearing applications for space. NASA and others are developing relatively low ratio (less than 25:1 per stage) concentric magnetic gearing for aeronautics applications. Space applications demand high speed-reduction ratio (often more than 1000:1) and high specific torque (>50 Nm/kg), operation in environmental temperatures down to -230C (40K), operation in low-atmosphere or hard vacuum, with high reliability and energy efficiency. Phase I work would include identifying the most suitable magnetic gear topologies to meet these space application needs, defining the technology development challenges including thermal and structural issues, advancing the most critical aspects of the technology, and producing a low-fidelity prototype to prove the feasibility of the concept(s).
• Perception systems and algorithms with a path toward flight for the lunar surface capable of operating in the harsh lighting conditions that might include high dynamic range, shadowed regions, low angle illumination, and opposition effects
• Lunar regolith terramechanical modeling tools and simulations, especially tools that integration with existing commercial and open source robotic analysis and simulation tools.
• Rover embedding and entrapment detection and escape approaches including slip monitoring, regolith sensing/modeling, low ground pressure wheels and soft soil tolerant mobility architectures.

For all the above, it is desired to have been demonstrated in, or have a clear path to operating in, the lunar environment. NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link:  https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

References

NASA is still formulating its approach to future lunar science and exploration. The current plan is to start with small commercial landers (<100kg) beginning as early as 2019, with relatively high launch cadence (2+ launches/year). In the future, NASA seeks to build mid-to-large landers, with an eye on human-rated landers with a first mid-sized lander planned for 2022.

Further information can be found at the following:

• How to survive a Lunar night: https://www.sciencedirect.com/science/article/pii/S0032063310003065 [79]
• Apollo Experience Report - Thermal Design of Apollo Lunar Surface Experiments Package: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19720013192.pdf [80]
• The Lunar Environment: https://www.lpi.usra.edu/publications/books/lunar_sourcebook/pdf/Chapter03.pdf [81]
• Commercial Lunar Payload Services - CLPS: https://www.fbo.gov/index?s=opportunity&mode=form&id=46b23a8f2c06da6ac08e1d1d2ae97d35&tab=core&_cview=0 [82]
• Survive and Operate Through the Lunar Night Workshop: https://www.hou.usra.edu/meetings/survivethenight2018/ [83]
• NASA's Exploration Campaign: Back to the Moon and on to Mars: https://www.nasa.gov/feature/nasas-exploration-campaign-back-to-the-moon-and-on-to-mars [84]
• NASA Exploration Campaign: https://www.nasa.gov/sites/default/files/thumbnails/image/nasa-exploration-campaign.jpg [85]

Additional information on NASA's interest in landers that might host the rovers can be found at the following:

• NASA Seeks Ideas to Advance toward Human-Class Lunar Landers (https://www.nasa.gov/feature/nasa-seeks-ideas-to-advance-toward-human-class-lunar-landers [86])
• Lunar Surface Transportation Capability Request for Information (RFI) (https://govtribe.com/project/lunar-surface-transportation-capability-request-for-information-rfi [87])

Magnetic gearing references:

• Tlali, P. M., Wang, R-J., and Gerber, S., “Magnetic gear technologies: A review,” 2014 Intl. Conference on Electrical Machines, p. 544-550, Berlin, Germany, Sept. 2 – 5, 2014.
• Justin J. Scheidler, Vivake M. Asnani, and Thomas F. Tallerico, “Overview of NASA’s Magnetic Gears Research,” presented at the AIAA / IEEE Electric Aircraft Technology Symposium, Cincinnati, Ohio, July 12 – 13, 2018.
• Vivake M. Asnani, Justin J. Scheidler, and Thomas F. Tallerico, “Magnetic Gearing Research at NASA,” presented at the 74th Annual Forum of the American Helicopter Society, Phoenix, AZ, May 14 – 17 2018.
• Aaron D. Anderson and Vivake M. Asnani, "Concentric Magnetic Gearing - State of the Art and Empirical Trends", NASA TM, in-press.

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software

Desired Deliverables Description

Example deliverables coming from a successful phase II within this subtopic, might including some of the following:

• Designs of cryo-capable or dust tolerant mechanisms motor controllers with test data and prototypes
• Prototype rovers or scale versions of prototype rovers showing novel mobility architecture for escaping entrapment in regolith
• Software algorithms including demonstrating slip detection or image processing in harsh lunar lighting conditions
• Software packages either standalone or integrated with commercially available or open-source robotic simulation packages (preferred).

NASA is also interested in technologies demonstrations that could serve as payloads on commercial landers at the end of phase II.

State of the Art and Critical Gaps

Current state of the art in robotic surface mobility is the MER/MSL (Mars Exploration Rover/Mars Science Laboratory) rovers for Mars and the Chinese Chang'e on the moon. Since the end of the NASA Constellation program in 2011, there has been only small pockets of technology development for the lunar surface within NASA and other space agencies, plus the small business/academic communities.

The specific areas noted above for targeted development (mechanisms, cryoactuators, magnetic gearing, perception systems, terramechanics simulations and novel mobility architectures) are all of specific interest as they are specific challenges unique to the lunar surface and lunar poles specifically.

Magnetic gearing has become practical in recent years due to the availability of high energy density magnets and design topologies that conserve volume. As a result, there has been an exponential growth in R&D for Earth applications like wind/wave energy generators and hybrid vehicle power-trains.

Relevance / Science Traceability

This SBIR resides within STMD as a vehicle for development of technology objectives. It is expected that successful projects would infuse technology into either the STMD Game Changing Development (GCD) or Technology Demonstration Missions (TDM) programs. Technology could also be infused into joint efforts involving STMD's partners (other mission directorates, other government agencies, and the commercial sector). Flights for these technology missions could be supported on small commercial lunar landers (SMD) or possibly mid-size NASA lunar landers (HEOMD).

Potential customers:

• Autonomy and robotics
• Robotic ISRU missions
• Payloads for Commercial Lunar Payload Services landers
• Commercial vendors

Future prospecting/mining operations

Scope Title

Free-Space Optical Communications Technologies

Scope Description

This Free-space Long Range Optical Communications subtopic seeks innovative technologies for advancing free-space optical communications by pushing future data volume returns to and from space missions in multiple domains with return data-rates > 100 Gbit/s (cis-lunar, i.e. Earth or lunar orbit to ground), > 10 Gbit/s (Earth-sun L1 and L2), >1 Gbit/s per AU-squared (deep space), and >1 Gbit/s (planetary lander to orbiter) and forward data-rates > 25 Mb/s at ranges extending from the Moon to Mars. Innovative technologies should target improved efficiency, reliability, robustness, and longevity for existing or novel state-of-the-art flight laser communication systems. Photon-counting sensitivity, near infrared (NIR), space-flight worthy detectors/detector arrays for supporting laser ranging for potential navigation and science are of particular interest. Ground-based technologies targeting high power, NIR and intensity-modulated lasers with fast rise times and low timing jitter (sub-nanosecond) are needed to support high forward data-rates and laser ranging.

Proposals are sought in the following specific areas:

Flight Laser Transceivers

Low-mass, high-Effective Isotropic Radiated Power (EIRP) laser transceivers for links over planetary distances with:

• 30 to 50 cm clear aperture diameter telescopes for laser communications
• Targeted mass of opto-mechanical assembly per aperture area, less than 100 kg/square-meter
• Cumulative wave-front error and transmission loss not to exceed 2 dB.
• Advanced thermal-mechanical designs to withstand planetary launch loads and flight temperatures by the optics and structure, at least -20° C to 70° C operational range
• Design to mitigate stray light while pointing transceiver 3 degrees from edge of sun
• Survive direct sun pointing for extended duration

Transceivers fitting the above characteristics should support robust link acquisition tracking and pointing characteristics, including point-ahead implementation from space for beacon assisted and/or "beaconless" architectures. Innovative solutions for mechanically stiff, light-weighted thermally stable structural properties are sought.

• Pointing loss allocations not to exceed 1 dB (pointing errors associated loss of irradiance at target less than 20%)
• Receiver field-of-view of at least 1 milliradian angular radius for beacon assisted acquisition, tracking and pointing
• As a goal additional focal plane with field-of-view to support on-board astrometry is desired
• Beaconless pointing subsystems for operations beyond 3 AU
• Assume integrated spacecraft micro-vibration angular disturbance of 150 micro-radians (<0.1 Hz to ~500 Hz)

Low complexity small footprint agile laser transceivers for bi-directional optical links (> 1-10 Gbit/second at a nominal link range of 1000-20000 km) for planetary lander/rover to orbiter and/or space-to-space cross links.

• Disruptive low Size, Weight and Power (SWaP) technologies that can operate reliably in space over extended mission duration
• Vibration isolation/suppression systems that will integrate to the optical transceiver in order to reject high frequency base disturbance by at least 50 dB
• Desire integrated launch locks and latching mechanism
• Low burden (mass, power, volume)
• Robust for space flight
• Should afford limited +/- 5 mrad - +/-12 mrad actuated field-of-regard for the optical line of sight of the transceiver

Flight Laser Transmitters

High-gigabit/s laser transmitters

• 1550 nm wavelength
• Lasers, electronics and optical components ruggedized for extended space operations
• High rate 10-100 Gb/s for cis-lunar
• 1 Gb/s for deep-space
• Integrated hardware with embedded software/firmware for innovative coding/modulation/interleaving schemes that are being developed as a part of the Consultative Committee for Space Data Systems (CCSDS)

High peak-to-average power laser transmitters for regular or augmented M-ary PPM modulation with M=4, 8, 16, 32, 64, 128, 256 operating at NIR wavelengths, preferably 1550 nm with average powers from 5 - 50 W 

• Sub-nanosecond pulse
• Low pulse jitter
• Long lifetime and reliability operating in space environment ( > 5 and as long as 20 years)
• High modulation and polarization extinction ratio with 1-10 GHz line width

Space-qualifiable wavelength division multiplexing transmitters and amplifiers with 4 to 20 channels and average output power > 20W per channel; peak-to-average power ratios >200; >10 Gb/s channel modulation capability.

• >20% wall-plug efficiency (DC-to-optical, including support electronics) with description of approach for stated efficiency of space-qualifiable lasers. Multi-watt Erbium Doped Fiber Amplifier (EDFA), or alternatives, with high gain bandwidth (> 30nm, 0.5 dB flatness) concepts will be considered.
• Radiation tolerance better than 50 krad is required (including resilience to photo-darkening).

Receivers/Sensors

Space-qualifiable high-speed receivers and low light level sensitive acquisition, tracking, pointing, detectors, and detector arrays

• NIR wavelengths: 1064nm and/or 1550 nm
• Sensitive to low irradiance incident at flight transceiver aperture (~ fW/m2 to pW/m2) detection
• Low sub-nanosecond timing jitter and fast rise time
• Novel hybridization of optics and electronic readout schemes with in-built pre-processing capability
• Characteristics compatible with supporting time-of-flight or other means of processing laser communication signals for high precision range and range rate measurements
• Tolerant to space radiation effects, total dose > 50 krad, displacement damage and single event effects

Novel technologies and accessories

Narrow Bandpass Optical Filters

• Space-qualifiable, sub-nanometer to nanometer, noise equivalent bandwidth with ~90% throughput, large spectral range out-of-band blocking (~ 40 dB)
• NIR wavelengths from 1064 – 1550 nm region, with high transmission through Earth’s atmosphere
• Reliable tuning over limited range

Novel Photonics Integrated Circuit (PIC) devices targeting space applications with objective of reducing size, weight and power of modulators, without sacrificing performance. Proposed PIC solutions should allow improved integration and efficient coupling to discrete optics, when needed.

Concepts for offering redundancy to laser transmitters in space

• Optical fiber routing of high average powers (10’s of watts) and high peak powers (1-10 kW)
• Redundancy in actuators and optical components
• Reliable optical switching

Ground Assets for Optical Communication

Low cost large aperture receivers for faint optical communication signals from deep space subsystem technologies:

• Demonstrate innovative subsystem technologies for >10 m diameter deep-space ground collector
• Capable of operating to within 3 degrees of solar limb
• Better than 10 micro radian spot size (excluding atmospheric seeing contribution)
• Desire demonstration of low-cost primary mirror segment fabrication to meet a cost goal of less than $35 K per square meter
• Low-cost techniques for segment alignment and control, including daytime operations
• Partial adaptive correction techniques for reducing the field of view required to collect signal photons under daytime atmospheric "seeing" conditions
• Innovative adaptive techniques not requiring a wavefront sensor and deformable mirror of particular interest
• Mirror cleanliness monitor and control systems
• Active metrology systems for maintaining segment primary figure and its alignment with secondary optics
• Large core diameter multi-mode fibers with low temporal dispersion for coupling large optics to detectors remote (30-50 m) from the large optics

1550 nm sensitive photon counting detector arrays compatible with large aperture ground collectors with a means of coupling light from large aperture diameters to reasonably- sized detectors/detector arrays, including optical fibers with acceptable temporal dispersion

• Integrated time tagging readout electronics for >5 giga-photons/s incident rate
• Time resolution <50 ps at 1-sigma
• Highest possible single photon detection efficiency, at least 50% at highest incident rate
• Total detector active area > 0.3 - 1 mm2
• Integrated dark rate < 3 mega-count/s.

Cryogenic optical filters

• Operate at 40 K with sub-nanometer noise equivalent bandwidths
• 1550 nm spectral region, transmission losses < 0.5 dB, clear aperture
• >35 mm, and acceptance angle > 40 milliradians with out-of-band rejection of > 65 dB from 0.4 - 5 microns.

Multi-kilowatt laser transmitters for use as ground beacon and uplink laser transmitters

• Near infrared wavelengths in 1.0 or 1.55 micrometer spectral region
• Capable of modulating with narrow nanosecond and sub-nanosecond rise times
• Low-timing jitter and stable operation
• High speed real-time signal processing of serially concatenated pulse position modulation operating at a few bits per photon with user interface outputs
• 15-60 MHz repetition rates

For all technologies lowest cost for small volume production (5 to 20 units) is a driver. Research must convincingly prove technical feasibility (proof-of-concept) during Phase I, ideally with hardware deliverables that can be tested to validate performance claims, with a clear path to demonstrating and delivering functional hardware meeting all objectives and specifications in Phase II.

References

https://www.nasa.gov/mission_pages/tdm/lcrd/index.html [89]

https://www.nasa.gov/directorates/heo/scan/opticalcommunications/illuma-t [90]

https://www.nasa.gov/feature/goddard/2017/nasa-laser-communications-to-provide-orion-faster-connections [91]

https://www.nasa.gov/mission_pages/tdm/dsoc/index.html [92]

Expected TRL or TRL range at completion of the project: TRL 2-3 Phase I for maturation to TRL 3-5 in Phase II

Desired Deliverables of Phase II

Prototype, Hardware, Software

Desired Deliverables Description

Models of components or assemblies for flight laser transceivers or Ground receivers

State of the Art and Critical Gaps

The State Of the Art (SOA) for Free-Space Optical Communications (FSOC) can be subdivided into near-earth (extending to cis- and trans-lunar distances) and planetary ranges with the Lagrange points falling in between.

Near Earth FSOC technology has completed a number of technology demonstrations from space and is more mature. Nonetheless, low size-weight power novel high speed 10-100 Gb/s space-qualified laser transmitters and receivers are sought. These transmitters and receivers can possibly be infused for deep space proximity links, such as landed assets on planetary surfaces to orbiting assets with distances of 5000-100000 km or inter-satellite links. Innovative light-weight space-qualified modems for handling multiple optical modulation schemes.

A technology demonstration for deep space FSOC is anticipated in the next decade. Critical gaps following a successful technology demonstration will be light-weighted 30-50 cm optical with a wide operational temperature range -20C to 50C over which wave front error and focus is stable. High peak-to-average power space qualified lasers with average powers of 20-50 W. Single photon-sensitive radiation-hardened flight detectors with high detection efficiency, fast rise times low timing jitter. The detector size should be able to cover 1 milliradian Field-Of-View (FOV) with an instantaneous FOV comparable to the transmitted laser beam width. Laser pointing control systems that operate with dim laser beacons transmitted from earth or use celestial beacon sources.

For Deep Space Optical Communications (DSOC) ground laser transmitters with high average power (kW class) but narrow line-widths (< 0.3 nm) and high variable repetition rates are required. Innovative optical coatings for large aperture mirrors that are compatible with near-sun pointing applications for efficiently collecting the signal and lowering background and stray light.

Relevance / Science Traceability

A number of FSOC-related NASA projects are ongoing with launch expected in the 2019-2022 time frame. The Laser Communication Relay Demonstration (LCRD) is an earth-to-geostationary satellite relay demonstration to launch in late 2019. The Illuma -T Project will extend the relay demonstration to include a Low Earth Orbit (LEO) node on the ISS in 2021. In 2022 the EM-2 Optical to Orion (O2O) demonstration will transmit data from the Orion crewed capsule as it travels to the Moon and back. In 2022 the DSOC Project technology demonstration will be hosted by the Psyche Mission spacecraft extending FSOC links to astronomical unit distances.

These missions are being funded by NASA's Space Technology Mission Directorate (STMD) Technology Demonstration Mission (TDM) Program and Human Exploration Operations Mission Directorate (HEOMD) Space Communications and Navigation (SCaN) Program.

Scope Title

Advanced Techniques for Trajectory Optimization

Scope Description

Future NASA missions will require precision landing, rendezvous, formation flying, cooperative robotics, proximity operations (e.g., servicing) and coordinated platform operations. This drives the need for increased precision in absolute and relative navigation solutions and more advanced algorithms for both ground and onboard navigation, guidance and control. This sub-topic seeks advancements in flight dynamics and navigation technology for applications in Earth orbit, lunar, and deep space that enables future NASA missions. In particular, technology relating to autonomous onboard navigation, guidance, and control, and trajectory optimization are solicited. See Reference 1 below for NASA Technical Area (TA) roadmaps:

• Low-thrust trajectory optimization in a multi-body dynamical environment (TA 5.4.2.1)
• Advanced deep-space trajectory design techniques. (TA 5.4.2.7) and rapid trajectory design near small bodies (TA 5.4.5.1)
• Tools and techniques for orbit/trajectory design for distributed space missions including constellations and formations (TA 11.2.6)

Proposals that leverage state-of-the-art capabilities already developed by NASA, or that can optionally integrate with those packages, such as the General Mission Analysis Tool (GMAT), Copernicus, Evolutionary Mission Trajectory Generator (EMTG), Mission Analysis Low-Thrust Optimization (MALTO), Monte, and Optimal Trajectories by Implicit Simulation (OTIS), or other available software tools are encouraged. Proposers who contemplate licensing NASA technologies are highly encouraged to coordinate with the appropriate NASA technology transfer offices prior to submission of their proposals.

References

1. NASA Space Technology Roadmaps (2015): https://www.nasa.gov/offices/oct/home/roadmaps/index.html [94]

2. General Mission Analysis Tool (GMAT): http://gmatcentral.org/display/GW/GMAT+Wiki+Home [95]

3. Evolutionary Mission Trajectory Generator (EMTG): https://software.nasa.gov/software/GSC-16824-1 [96]

4. Copernicus: https://www.nasa.gov/centers/johnson/copernicus/index.html [97]

5. Mission Analysis Low-Thrust Optimization (MALTO): https://software.nasa.gov/software/NPO-43625-1 [98]

6. Monte: https://montepy.jpl.nasa.gov/ [99]

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Software, Research

Desired Deliverables Description

Phase 1 research should be conducted to demonstrate technical feasibility, with preliminary software being delivered for NASA testing, as well as show a plan towards Phase 2 integration. Phase 2 new technology development efforts shall deliver components at the Technology Readiness Level (TRL) 5-6 level with mature algorithms and software components complete and preliminary integration and testing in an operational environment.

State of the Art and Critical Gaps

Algorithms and software for rapid and robust preliminary and high-fidelity design and optimization of low thrust trajectories in a multi-body dynamical environment (such as cislunar space) currently do not exist. Designing trajectories for these types of missions relies heavily on hands-on work by very experienced people. That works reasonably well for designing a single reference trajectory but not as well for exploring trade spaces or when designing thousands of trajectories for a Monte-Carlo or missed-thrust robustness analysis.

Relevance / Science Traceability

• Lunar Orbital Platform-Gateway
• WFIRST
• Europa Clipper
• Lucy
• Psyche

Trajectory design for these complex missions can take weeks or months to generate a single reference trajectory. Providing algorithms and software to speed up this process will enable missions to more fully explore trade spaces and more quickly respond to changes in the mission.

Scope Title

Autonomous Onboard Spacecraft Navigation, Guidance and Control

Scope Description

Future NASA missions require precision landing, rendezvous, formation flying, proximity operations (e.g., servicing and assembly), non-cooperative object capture and coordinated platform operations in Earth orbit, cislunar space, libration orbits and deep space. These missions require a high degree of autonomy. The subtopic seeks advancements in autonomous spacecraft navigation and maneuvering technologies for applications in Earth orbit, lunar, cislunar, libration and deep space to reduce dependence on ground-based tracking, orbit determination and maneuver planning. See Reference 1 for NASA Technical Area (TA) roadmaps:

• Advanced autonomous spacecraft navigation techniques including devices and systems that support significant advances in independence from Earth supervision while minimizing spacecraft burden by requiring low power and minimal mass and volume (TA 5.4.2.4, TA 5.4.2.6, TA 5.4.2.8).
• Onboard spacecraft trajectory planning and optimization algorithms for real-time mission re-sequencing, on-board computation of large divert maneuvers (TA 5.4.2.3, TA 5.4.2.5, TA 5.4.2.6, TA 9.2.6) primitive body/lunar proximity operations and pinpoint landing (TA 5.4.6.1), including the concept of robust onboard trajectory planning and optimization algorithms that account for system uncertainty (i.e., navigation errors, maneuver execution errors, etc.).
• Onboard relative and proximity navigation (TA 5.4.4) multi-platform relative navigation (relative position, velocity and attitude or pose) which support cooperative and collaborative space operations such as satellite servicing and in-space assembly.
• Rendezvous targeting (TA 4.6.2.1) Proximity Operations/Capture/ Docking Guidance (TA 4.6.2.2)
• Advanced filtering techniques (TA 5.4.2.4) that address rendezvous and proximity operations as a multi-sensor, multi-target tracking problem; handle non-Gaussian uncertainty; or incorporate multiple-model estimation.
• Advanced algorithms for safe precision landing on small bodies, planets and moons, including real-time three-dimensional (3D) terrain mapping (TA 9.2.81, 9.2.8.3), autonomous hazard detection and avoidance (TA 9.2.8.4), terrain relative navigation (TA 9.2.8.2), small body proximity operations (TA 9.2.8.8).
• Machine vision techniques to support optical/terrain relative navigation and/or spacecraft rendezvous/proximity operations.

Proposals that leverage state-of-the-art capabilities already developed by NASA, or that can optionally integrate with those packages, such as the Goddard Enhanced Onboard Navigation System (GEONS) (https://software.nasa.gov/software/GSC-14687-1 [100]), Navigator (http://itpo.gsfc.nasa.gov/wp-content/uploads/gsc_14793_1_navigator.pdf [101]), NavCube (https://goo.gl/bdobb9 [102]) or other available NASA hardware and software tools are encouraged.  Proposers who contemplate licensing NASA technologies are highly encouraged to coordinate with the appropriate NASA technology transfer offices prior to submission of their proposals.

References

1. NASA Space Technology Roadmaps (2015): https://www.nasa.gov/offices/oct/home/roadmaps/index.html [94]

2. Goddard Enhanced Onboard Navigation System (GEONS), (https://software.nasa.gov/software/GSC-14687-1 [100]), (https://goo.gl/TbVZ7G [103])

3. Mission Analysis, Operations, and Navigation Toolkit Environment (MONTE), (https://montepy.jpl.nasa.gov/ [99])

4. Navigator (http://itpo.gsfc.nasa.gov/wp-content/uploads/gsc_14793_1_navigator.pdf [101])

5. NavCube (https://goo.gl/bdobb9 [102])

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Phase 1 research should be conducted to demonstrate technical feasibility, with preliminary software being delivered for NASA testing, as well as show a plan towards Phase 2 integration. For proposals that include hardware development, delivery of a prototype under the Phase 1 contract is preferred, but not necessary. Phase 2 new technology development efforts shall deliver components at the TRL 5-6 level with mature algorithms and software components complete and preliminary integration and testing in an operational environment.

State of the Art and Critical Gaps

Currently navigation, guidance and control functions rely heavily on the ground for tracking data, data processing and decision making. As NASA operates farther from Earth and performs more complex operations requiring coordination between vehicles, round trip communication time delays make it is necessary to reduce reliance on Earth for navigation solutions and maneuver planning. Spacecraft that arrive at a near-Earth asteroid (NEA) or a planetary surface, may have limited
ground inputs and no surface or orbiting navigational aids. NASA currently does not have the navigational, trajectory and attitude flight control technologies that permit fully autonomous approach, proximity operations and landing without navigation support from Earth.

Relevance / Science Traceability

• Lunar Orbital Platform-Gateway
• Orion Multi-Purpose Crew Vehicle
• Wide Field Infrared Survey Telescope (WFIRST)
• Europa Clipper
• Lucy
• Psyche

These complex, deep space missions require a high degree of autonomy. The technology produced in this subtopic enables these kinds of missions by reducing or eliminating reliance on the ground for navigation and maneuver planning. The subtopic aims to reduce the burden of routine navigational support and communications requirements on network services, increase operational agility, and enable near real-time re-planning and opportunistic science. It also aims to enable classes of missions that would otherwise not be possible due to round-trip light time constraints.

Scope Title

Conjunction Assessment Risk Analysis (CARA)

Scope Description

The U.S. Space Surveillance Network currently tracks more than 22,000 objects larger than 10 centimeters and the number of objects in orbit is steadily increasing which causes an increasing threat to human spaceflight and robotic missions in the near-Earth environment. The NASA Conjunction Assessment Risk Analysis (CARA) team receives screening data from the 18th Space Control Squadron concerning predicted close approaches between NASA satellites and other space objects.  CARA determines the risk posed by those events and recommends risk mitigation strategies, including collision avoidance maneuvers, to protect NASA non-human-spaceflight assets in Earth orbit. The ability to perform CARA more accurately and rapidly will improve space safety for all near-Earth operations. This subtopic seeks innovative technologies to improve the CARA process including (see Reference 1 for NASA Technical Area (TA) roadmaps):

• Event evolution prediction methods, models and algorithms with improved ability to predict characteristics for single and ensemble risk assessment, especially using artificial intelligence/machine learning (TA 5.5.3).
• Methods for combining commercial data (observations or ephemerides) with 18 SPCS –derived solutions (available as Vector Covariance Messages, Conjunction Data Messages, or Astrodynamics Support Workstation output) to create a single improved orbit determination solution including more data sources.

References

1. NASA Space Technology Roadmaps (2015): https://www.nasa.gov/offices/oct/home/roadmaps/index.html [94]
2. NASA Conjunction Assessment Risk Analysis (CARA) Office: https://satellitesafety.gsfc.nasa.gov/cara.html [104]

   3. NASA Orbital Debris Program Office: https://www.orbitaldebris.jsc.nasa.gov/ [105]

3. Newman, Lauri, K., "The NASA robotic conjunction assessment process: Overview and operational experiences," Acta Astronautica, Vol. 66, Issues 7-8, Apr-May 2010, pp. 1253-1261, https://www.sciencedirect.com/science/article/pii/S0094576509004913 [106].
4. Newman, Lauri K., et al. "Evolution and Implementation of the NASA Robotic Conjunction Assessment Risk Analysis Concept of Operations." (2014). https://ntrs.nasa.gov/search.jsp?R=20150000159 [107]
5. Newman, Lauri K., and Matthew D. Hejduk. "NASA Conjunction Assessment Organizational Approach and the Associated Determination of Screening Volume Sizes." (2015). https://ntrs.nasa.gov/search.jsp?R=20150011461 [108]

Expected TRL or TRL range at completion of the project: 2 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Software, Research

Desired Deliverables Description

Phase 1 research should be conducted to demonstrate technical feasibility, with preliminary software being delivered for NASA testing, as well as show a plan toward Phase 2 integration. Phase 2 new technology development efforts shall deliver components at the TRL 5-6 level with mature algorithms and software components complete and preliminary integration and testing in a quasi-operational environment.

State of the Art and Critical Gaps

Current state of the art has been adequate in performing conjunction assessment and collision mitigation for space objects that fall under the high interest events (HIE). With the incorporation of the Space Fence, the number of objects tracked and assessed for conjunctions will increase by one or more orders of magnitude, this presents a critical gap in which current approaches may not suffice. Thus, smarter ways to perform conjunction analysis and assessments such as methods for bundling events and performing ensemble risk assessment, Middle-duration risk assessment (longer duration than possible for discrete events but shorter than decades-long analyses that use gas dynamics assumptions), Improved Conjunction Assessment (CA) event evolution prediction, Machine learning / Artificial Intelligence (AI) applied to CA risk assessment parameters and/or event evolution are needed. The decision space for collision avoidance relies on not only the quality of the data (state and covariance) but also the tools and techniques for conjunction assessment.

Collision avoidance maneuver decisions are based on predicted close approach distance and probability of collision. The accuracy of these numbers depend on underlying measurements and mathematics used in estimation. Current methods assume Gaussian distributions for errors and that all objects are shaped like cannon balls for non-gravitational force computations. These assumptions and others cause inaccurate estimates which can lead decision makers to perform unnecessary collision avoidance maneuvers, thus wasting propellant. Better techniques are needed for orbit prediction and covariance characterization and propagation. Better modeling of non-gravitational force effects is needed to improve orbit prediction. Modeling of non-gravitational forces relies on knowledge of individual object characteristics.

Relevance / Science Traceability

This technology is relevant and needed for all human spaceflight and robotic missions in the near-Earth environment. The ability to perform CARA more accurately will improve space safety for all near-Earth operations, improve operational support by providing more accurate and longer term predictions and reduce propellant usage for collision avoidance maneuvers.

Scope Title

Revolutionary Concepts

Scope Description

NASA seeks revolutionary transformational communications technologies, for lunar exploration and beyond, that emphasize not only dramatic reduction in system size, mass and power but also dramatic implementation and operational cost savings while improving overall communications architecture performance. The proposer is expected to identify new ideas, create novel solutions and execute feasibility demonstrations. Emphasis for this subtopic is on the far-term (≈10yrs.) insofar as mission insertion and commercialization but it is expected that the proposer proves fundamental feasibility via prototyping within the normal scope of the SBIR program. The transformational communications technology development will focus research in the following areas:

• Systems optimized for energy efficiency (information bits per unit energy)
• Hybridization of communications and sensing systems to maximize performance and minimize Size, Weight and Power (SWaP), especially for harsh environments
• Advanced materials; smart materials; electronics embedded in structures; functional materials; graphene-based electronics/detectors
• Techniques to overcome traditional analog-to-digital converter speed and power consumption limitations
• Technologies that address flexible, scalable digital/optical core processing topologies to support both RF and optical communications in a single terminal
• Nanoelectronics and nanomagnetics; quantum logic gates; single electron computing; superconducting devices; technologies to leapfrog Moore’s law.
• Energy harvesting technologies to enhance space communication system efficiency
• Human/machine and brain-machine interfacing to enable new communications paradigms; the convergence of electronic engineering and bio-engineering; neural signal interfacing
• Quantum communications, methods for probing quantum phenomenon, methods for exploiting exotic aspects of quantum theory.

The research should be conducted to demonstrate theoretical and technical feasibility during the Phase I and Phase II development cycles and be able to demonstrate an evolutionary path to insertion within approximately 10 years. Delivery of a prototype of the most critically enabling element of the technology for NASA testing at the completion of the Phase II contract is expected.

Phase I deliverables shall include a final report describing theoretical analysis and prototyping concepts. The technology should have eventual commercialization potential. For Phase II consideration, the final report should include a detailed path towards Phase II prototype hardware.

References

https://sbir.nasa.gov/sites/default/files/Presentation15_CharlesNiederhaus.pdf [110]

https://www.nasa.gov/pdf/675092main_SCaN_ADD_Executive_Summary.pdf [111]

Expected TRL or TRL range at completion of the project: 2 to 4

Desired Deliverables of Phase II

Prototype, Analysis, Research

Desired Deliverables Description

The proposer is expected to identify new ideas, create novel solutions and execute feasibility demonstrations. Emphasis for this subtopic is on the far-term (≈10yrs.) insofar as mission insertion and commercialization but it is expected that the proposer proves fundamental feasibility via prototyping within the normal scope of the SBIR program.

State of the Art and Critical Gaps

While according to the Business R&D and Innovation Survey of the $323 billion of research and development performed by companies in the United States in 2013, Information and Computing Technology industries accounted for 41%. But it must be understood that the majority of these investments seek short term returns and that most of the investment is in computer technology, cloud computing and networking, semiconductor manufacturing, etc. - not new and futuristic "over-the-horizon" technologies with uncertain returns-on-investment. As a concrete example, deep-space mission modeling indicates a need for a 10X improvement in data rate per decade out to 2040. How will that be achieved? To some extent that goal will be achieved by moving to Ka-band and optical communications and perhaps antenna arraying on a massive scale. But given the ambitiousness of the goal, disruptive technologies like what is being sought here, will be required.

Relevance / Science Traceability

NASA seeks revolutionary, transformational communications technologies that emphasize not only dramatic reduction in system size, mass, and power but also dramatic implementation and operational cost savings while improving overall communications architecture performance. This is a broad sub-topic expected to identify new ideas, create novel solutions and execute feasibility demonstrations. Emphasis for this subtopic is on the far-term (≈10yrs.) insofar as mission insertion and commercialization but it is expected that the proposer proves fundamental feasibility via prototyping within the normal scope of the SBIR program.

Scope Title

Lunar Cognitive Capabilities

Scope Description

NASA's Space Communication and Navigation (SCaN) program seeks innovative approaches to increase mission science data return, improve resource efficiencies for NASA missions and communication networks and ensure resilience in the unpredictable space environment. The Cognitive Communication subtopic specifically focuses on advances in space communication driven by on-board data processing and modern space networking capabilities. A cognitive system is envisioned to sense, detect, adapt, and learn from its experiences and environment to optimize the communications capabilities for the user mission satellite or network infrastructure. The underlying need for these technologies is to reduce both the mission and network operations burden.

Examples of these cognitive capabilities include:

• Link technologies - reconfiguration and autonomy, maximizing use of bandwidth while avoiding interference
• Network technologies - robust inter-satellite links, data storage/forwarding, multi-node routing in unpredictable environments
• System technologies - optimal scheduling techniques for satellite and surface relays in distributed and real-time environments

Through Space Policy Directive-1, NASA is committed to landing American astronauts on the Moon by 2024. In support of this goal, cognitive communication techniques are needed for lunar communication satellite and surface relays. Cognitive agents operating on lunar elements will manage communication, provide diagnostics, automate resource scheduling, and dynamically update data flow in response to the types of data flowing over the lunar network. Goals of this capability are to improve communications efficiency, mitigate channel impairments, and reduce operations complexity and cost through intelligent and autonomous communications and data handling.

Examples of research and/or technology development include:

• On-board processing technology and techniques to enable data switching, routing, storage, and processing on a relay spacecraft
• Data-centric, decentralized network data routing and scheduling techniques that are responsive to quality of service metrics
• Simultaneous wideband sensing and communications for S-, X-, and Ka-bands, coupled with algorithms that learn from the environment
• Artificial intelligence and machine learning algorithms applied to optimize space communication links, networks, or systems
• Flexible communication platforms with novel signal processing technology to support cognitive approaches
• Other innovative, related areas of interest to the field of cognitive communications

Proposals to this subtopic should consider application to a lunar communications architecture consisting of surface assets (e.g., astronauts, science stations, surface relays), lunar communication relay satellites, Gateway, and ground stations on Earth. The lunar communication relay satellites require technology with low size, weight, and power attributes suitable for small satellite (e.g., 50kg) or cubesat operations. Proposed solutions should highlight advancements to provide the needed communications capability while minimizing use of on-board resources such as power and propellant. Proposals should consider how the technology can mature into a successful demonstration in the lunar architecture.

References

Several related reference papers and articles include:

• "NASA Explores Artificial Intelligence for Space Communications"
  • https://www.nasa.gov/feature/goddard/2017/nasa-explores-artificial-intelligence-for-space-communications [113]
• "Implementation of a Space Communications Cognitive Engine"
  • https://ntrs.nasa.gov/search.jsp?R=20180002166 [114]
• "Reinforcement Learning for Satellite Communications: From LEO to Deep Space Operations"
  • https://ieeexplore.ieee.org/document/8713802 [115]
• "Cognitive Communications and Networking Technology Infusion Study Report"
  • https://ntrs.nasa.gov/search.jsp?R=20190011723 [116]
• "Multi-Objective Reinforcement Learning-based Deep Neural Networks for Cognitive Space Communications"
  • https://ntrs.nasa.gov/search.jsp?R=20170009153 [117]
• "Assessment of Cognitive Communications Interest Areas for NASA Needs and Benefits"
  • https://ntrs.nasa.gov/search.jsp?R=20170009386 [118]
• "Architecture for Cognitive Networking within NASAs Future Space Communications Infrastructure"
  • https://ntrs.nasa.gov/search.jsp?R=20170001295 [119]
• "Modulation Classification of Satellite Communication Signals Using Cumulants and Neural Networks"
  • https://ntrs.nasa.gov/search.jsp?R=20170006541 [120]

A related conference, co-sponsored by NASA and the Institute of Electrical and Electronics Engineers (IEEE), the Cognitive Communications for Aerospace Applications Workshop, has additional information available at: http://ieee-ccaa.com/ [121]

Expected TRL or TRL range at completion of the project: 4 to 6

Desired Deliverables of Phase II

Prototype, Hardware, Software

Desired Deliverables Description

Phase I will study technical feasibility, infusion potential for lunar operations, clear/achievable benefits and show a path towards a Phase II implementation. Phase I deliverables can include a feasibility assessment and concept of operations of the research topic, simulations and/or measurements, validation of the proposed approach to develop a given product (TRL 3-4) and a plan for further development of the specific capabilities or products to be performed in Phase II. Early development, integration, test, and delivery prototype hardware/software is encouraged but not necessary.

Phase II will emphasize hardware/software development with delivery of specific hardware or software product for NASA targeting demonstration operations on a small satellite or cubesat platform. Phase II deliverables include a working prototype (engineering model) of the proposed product/platform or software, along with documentation of development, capabilities, and measurements, and related documents and tools as necessary for NASA to modify and use the cognitive software capability or hardware component(s). Hardware prototypes shall show a path towards flight demonstration, such as a flight qualification approach and preliminary estimates of thermal, vibration, and radiation capabilities of the flight hardware. Software prototypes shall be implemented on platforms that have a clear path to a flight qualifiable platform. Opportunities and plans should be identified for technology commercialization. Software applications and platform/infrastructure deliverables for software defined radio platforms shall be compliant with the latest NASA standard for software defined radios, the Space Telecommunications Radio System (STRS), NASA-STD-4009 and NASA-HNBK-4009.

State of the Art and Critical Gaps

To summarize NASA Technology Roadmap TA5: "As human and science exploration missions move further from Earth and become increasingly more complex, they present unique challenges to onboard communications systems and networks...Intelligent radio systems will help manage the increased complexity and provide greater capability to the mission to return more science data...Reconfigurable radio systems...could autonomously optimize the RF links, network protocols, and modes used based on the needs of the various mission phases. A cognitive radio system would sense its RF environment and adapt and learn from its various configuration changes to optimize the communications links throughout the system in order to maximize science data transfer, enable substantial efficiencies, and reduce latency. The challenges in this area are in the efficient integration of different capabilities and components, unexpected radio or system decisions or behavior, and methods to verify decision-making algorithms as compared to known, planned performance."

The technology need for the lunar communication architecture includes:

• Data routing from surface assets to a lunar communication relay satellite, where data is unscheduled, a-periodic, and ad-hoc
• Data routing between lunar relay satellites as necessary to conserve power, route data to Earth, and meet quality of service requirements
• Efficient use of lunar communication spectrum while co-existing with future/current interference sources
• On-demand communication resource scheduling
• Multi-hop, delay tolerant routing

Critical gaps between the state of the art and the technology need include:

• Implementation of artificial intelligence and machine learning techniques on SWaP-constrained platforms
• Integrated wide-band sensing and narrow-band communication on the same radio terminal
• Inter-satellite networking and routing, especially in unpredictable and unscheduled environments
• On-demand scheduling technology for communication links
• Cross-layer optimization approaches for optimum communication efficiency at a system level

Relevance / Science Traceability

Cognitive technologies are critical for the lunar communications architecture. The majority of lunar operations will be run remotely from Earth, which could require substantial coordination and planning as NASA, foreign space agencies, and commercial interests all place assets on the Moon. As lunar communications and networks become more complex, cognition and automation are essential to mitigate complexity and reduce operations costs. Machine learning will configure networks, choose radio configurations, adjust for impairments and failures, and monitor short and long term performance for improvements.

Scope Title

Guidance, Navigation, and Control

Scope Description

NASA seeks innovative, groundbreaking, and high impact developments in spacecraft guidance, navigation, and control technologies in support of future science and exploration mission requirements. This subtopic covers mission enabling technologies that have significant Size, Weight and Power, Cost, and Performance (SWaP-CP) improvements over the state-of-the-art Commercial Off-The-Shelf (COTS) capabilities in the areas of Spacecraft Attitude Determination and Control Systems, Absolute and Relative Navigation Systems, and Pointing Control Systems, and Radiation-Hardened Guidance, Navigation, and Control (GNC) Hardware.

Component technology developments are sought for the range of flight sensors, actuators, and associated algorithms and software required to provide these improved capabilities. Technologies that apply to most spacecraft platform sizes will be considered.

Advances in the following areas are sought:

• Spacecraft Attitude Determination and Control Systems: Sensors and actuators that enable <0.1 arcsecond level pointing knowledge and arcsecond level control capabilities for large space telescopes, with improvements in size, weight, and power requirements.
• Absolute and Relative Navigation Systems: Autonomous onboard flight navigation sensors and algorithms incorporating both spaceborne and ground-based absolute and relative measurements. For relative navigation, machine vision technologies apply. Special considerations will be given to relative navigation sensors enabling precision formation flying, astrometric alignment of a formation of vehicles, robotic servicing and sample return capabilities, and other GNC techniques for enabling the collection of distributed science measurements.  In addition, flight sensors and algorithms that support onboard terrain relative navigation are of interest.
• Pointing Control Systems: Mechanisms that enable milliarcsecond class pointing performance on any spaceborne pointing platforms. Active and passive vibration isolation systems, innovative actuation feedback, or any such technology that can be used to enable other areas within this subtopic applies.
• Radiation-Hardened Hardware: GNC sensors that could operate in a high radiation environment, such as the Jovian environment.
• Fast-light or Exceptional-Point Enhanced Gyroscopes and Accelerometers: In conventional ring laser gyros, precision increases with cavity size and measurement time. However, by using Fast-Light (FL) media or Exceptional Points (EPs) in coupled resonators, an increase in gyro sensitivity can be achieved without having to increase size or measurement time, thereby increasing the time for standalone spacecraft navigation. (The increased precision also opens up new science possibilities such as measurements of fundamental physical constants, improving the sensitivity-bandwidth product for gravity wave detection, and tests of general relativity.) Prototype FL- or EP-enhanced gyros are sought that can be implemented in a compact rugged design that is tolerant to variations in temperature and G-conditions, with the ultimate goal of demonstrating decreased angular random walk.

Phase I research should be conducted to demonstrate technical feasibility as well as show a plan towards Phase II integration and component/prototype testing in a relevant environment. Phase II technology development efforts shall deliver component/prototype at the TRL 5–6 level consistent with NASA SBIR/STTR Technology Readiness Level (TRL) Descriptions. Delivery of final documentation, test plans, and test results are required. Delivery of a hardware component/prototype under the Phase II contract is preferred.

Proposals should show an understanding of one or more relevant science or exploration needs and present a feasible plan to fully develop a technology and infuse it into a NASA program.

This subtopic is for all mission enabling Guidance, Navigation, and Control technology in support of SMD missions and future mission concepts. Proposals for the development of hardware, software, and/or algorithm are all welcome. The specific applications could range from CubeSats/SmallSats, to ISS payloads, to flagship missions.

References

• 2017 NASA Strategic Technology Investment Plan: https://go.usa.gov/xU7sE [123]
• 2015 NASA Technology Roadmaps: https://go.usa.gov/xU7sy [124]

Expected TRL or TRL range at completion of the project: 4 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software

Desired Deliverables Description

Prototype hardware/software, documented evidence of delivered TRL (test report, data, etc.), summary analysis, supporting documentation.

State of the Art and Critical Gaps

Capability area gaps:

• Spacecraft GNC Sensors – Highly integrated, low power, low weight, rad-hard component sensor technologies, and multifunctional components.
• Spacecraft GNC Estimation and Control Algorithms – autonomous proximity operations algorithm, robust distributed vehicle formation sensing and control algorithms.

Relevance / Science Traceability

Science areas: Heliophysics, Earth Science, Astrophysics, and Planetary missions’ capability requirement areas:

• Spacecraft GNC Sensors – optical, RF, inertial, and advanced concepts for onboard sensing of spacecraft attitude and orbit states

Spacecraft GNC Estimation and Control Algorithms – Innovative concepts for onboard algorithms for attitude/orbit determination and control for single spacecraft, spacecraft rendezvous and docking, and spacecraft formations.

Scope Title

Expected Electric Field Prediction Methods in Fairing/Aircraft and Spacecraft Enclosures

Scope Description

NASA Launch Services program is responsible for ensuring the safety of NASA payloads on commercial rockets. NASA has also undertaken Gateway. This includes prediction and mitigation of hazardous electric fields created within the payload enclosure and similar areas of the rocket. NASA and industry have commonly used approximation methods to determine the average fields in enclosures. In the last decade the Launch Services Program (LSP) has funded studies to support quantification of electromagnetic field characterization in fairing cavities due to internal and external sources. By accurately predicting these fields, acoustic and thermal blanketing can be optimized for Radio Frequency (RF) attenuation and design changes can be quickly evaluated reducing schedule impacts. Cost savings can also be realized by reducing stringent radiated susceptibility requirements, and reliability improved by accurately predicting signal transmission/reception environments within enclosures. This methodology can also improve human exposure safety limits evaluations for manned vehicle enclosures with transmitting systems.

Initially, studies focused on computational methods using the recent advances in computing power and the improved efficiency of matrix based solutions provided by Graphics Processing Unit (GPU) computing. Results indicate solution of an integrated fairing is deterministic, but sensitive to small variation in structures, materials. As of yet, only the empty or sparse cavity can be reliably solved with 3D computational tools, even with large computing systems and the use of non-linear basis functions. Results also indicate that computational approximation methods such as physical optics and multilevel fast multipole are not reliable prediction methods within enclosures of this scale because of the underlying assumption sets that are inconsistent with enclosure boundaries. More recently, LSP has concentrated on statistically formulating a compilation of test/computational results to produce a maximum expected environment. Preliminary results are promising in the area of statistical bounding of the desired solution. The researched methodology should offer the following advantages over 3D computational and standard volume based approximation methods:

• Predict both statistical mean and maximum expected E field and/or common mode current.
• Consider the over-moded (electrically large conductive cavities) and under-moded (electrically smaller damped enclosures).
• Consider complex materials with multiple joined enclosures.
• Applications of this prediction methodology are far reaching and include shielding effectiveness and prediction of fields within a cavity enclosure due to internal transmitters and operating avionics.

To enable bounded solutions in electromagnetic environment prediction, proposals are solicited to develop technology that does the following:

• Bounds the expected peak electric field environment inside enclosures such as rocket fairings, and spacecraft enclosures. The method should include the technology required, the technique, as well as the necessary verification efforts.
• Develops a numerical or statistically based methodology for characterizing shielding effectiveness of enclosures with associated applicable apertures.
• Develops methods field enhancement/reduction based on thermal/acoustic blanketing and metal/composite components such as avionics and Payload Attached Fitting (PAF) structures.
• Develops preliminary user friendly modeling software that can be easily customized to support NASA-specific applications.

References

• [1] Paul G Bremner, Dawn Trout, Gabriel Vazquaz, Neda Nourshamsi, James C.West, and Charles F. Bunting, “Modal Q Factor and Modal Overlap of Electrically Small Avionics Boxes”, Proc. IEEE Intnl. Symp. EMC, Long Beach, August 2018
• [2] D. A. Hill, “Electromagnetic Fields in Cavities. Deterministic and Statistical Theories” John Wiley & Sons, Hoboken, New Jersey 2009
• [3] J. Ladbury, G. Koepke, and D. Camell, "Evaluation of the NASA Langley Research Center Mode-Stirred Chamber Facility," NIST, Technical Note 1508, 1999.
• [4] A. Schaffar and P. N. Gineste, "Application of the power balance methods to E- field calculation in the ARIANE 5 launcher payloads cavities," Presented at International Symposium on EMC, Long Beach, 2011, pp. 284-289.
• [5] D.H. Trout, "Electromagnetic Environment in Payload Fairing Cavities," Dissertation, University of Central Florida, 2012.
• [6] L. Kovalevsky, R.S. Langley, P. Besnier and J. Sol, “Experimental validation of the Statistical Energy Analysis for coupled reverberant rooms”, Proc. IEEE Intnl. Symp. EMC, Dresden, August 2015
• [7] Bremner, P.G, Vazquez, G., Trout, D.H and Cristiano, D.J., “Canonical Statistical Model for Maximum Expected Imission of Wire Conductor in an Aperture Enclosure”, Proc. IEEE Intnl. Symp. EMC, Ottawa, October 2016
• [8] G.B Tait, C. Hager, M.B. Slocum and M.O. Hatfiled, “On Measuring Shielding Effectiveness of Sparsely Moded Enclosures in a Reverberation Chamber”, IEEE Trans. on EMC, Volume: 55, Issue: 2, October 2012
• [9] P. Bremner, G.Vazquez, D. Trout, P. Edwards "Shielding Effectiveness: When to Stop Blocking and Start Absorbing", IEEE EMC International Symposium, New Orleans, July 2019

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Software, Research

Desired Deliverables Description

Phase I Deliverables:  Research, identify and evaluate candidate algorithms or concepts for electromagnetic field mapping of typical spacecraft and rocket enclosures. Demonstrate the technical feasibility, and show a path towards a computer model development. It should identify improvements over the current state of the art for both time/resource savings and systems development and the feasibility of the approach in a varied-enclosure environment. Lab-level demonstrations are required. Deliverables must include a report documenting findings.

Phase II Deliverables:  Emphasis should be placed on developing usable computer model and demonstrating the technology with under and over-moded conditions with testing. Deliverables shall include a report outlining the path showing how the technology could be matured and applied to mission-worthy systems, verification test results, computer model with user’s and other associated documentation. Deliverable of a functional computer model with associated software is expected at the completion of the Phase II contract.

State of the Art and Critical Gaps

Reliability of communications systems is critical for all spacecraft. Determining RF exposure limits in cavity environments is also critical. Given this criticality it is often desired to transmit and receive before separation from the launch vehicle where there is precise tracking information to improve the probability of signal capture. When the transmission or reception is in the launch vehicle fairing whether for pre-flight checks or during launch, the presence of the cavity surrounding the antennas causes significant uncertainties in the desired signal. In addition, there is a significant increase in the RF environment in which the spacecraft and launch vehicle hardware are exposed. Since hardware qualification testing is based on free space environments the higher fields in the cavity can lead to an increase mission risk of failure due to susceptible hardware. Prediction of fields within rectangular highly conductive over-moded chambers is well studied in the reverberation testing community; however, launch vehicle fairings are sometimes composite and always covered with acoustic damping materials that have unknown RF damping characteristics. There are also thermal materials surrounding launch vehicle and spacecraft avionics and instruments leading to further complications in defining the communication path losses and RF environment exposure and cavity mode underdamping characteristics where more research is needed especially in the layered wall covering case.

Determining the RF environment in the fairing cavity is a significant problem that affects every launched mission; even if transmission with the fairing is not planned, it has historically happened inadvertently and the effects of failed inhibits are required to be provided. Shielding effectiveness to external range and launch vehicle transmitters are also significantly affected by not only the material conductive properties, but also the characteristics of the penetrated cavity.

3D computational electromagnetic tools are limited by the size of the matrix required to solve the typical transmit frequency of at least 2GHz in a cavity with 5 meter diameters and over 10 meter length. The size of just modeling the fairing alone is daunting using method of moments (limited also by non-uniqueness for external radiators) and unachievable with finite difference frequency domain. When internal spacecraft and blanketing structures are added, the computational limits are quickly surpassed. Approximation techniques such as physical optics and multilevel fast multipole methods are limited by underlying assumptions that do not hold in cavity environments. Time domain techniques are not clearly fitted for frequency specific applications and have shown similar size/complexity limitations.

Substantially, new methods are needed to predict path loss, shielding effectiveness and RF environment in launch vehicle fairings and spacecraft cavities.

Relevance / Science Traceability

This subtopic is intended for STTR, but all NASA payloads, particularly those with hardware sensitive to electric fields, will benefit from launch and ascent risk reduction.

Scope Description

NASA seeks to develop quantum networks to support the transmission of quantum information for aerospace applications.  This distribution of quantum information could potentially be utilized in secure communication, sensor arrays and quantum computer networks.  Quantum communication may provide new ways to improve communication link security and availability through techniques such as quantum cryptographic key distribution.  Another area of benefit is the entanglement of distributed sensor networks to provide extreme sensitivity for applications such as astrophysics, planetary science and earth science.  Also of interest are ideas or concepts to support the communication of quantum information between quantum computers over significant free space distances (greater than 10km up to GEO) for space applications.  Technologies that are needed include quantum memory, quantum entanglement sources, quantum repeaters, high efficiency detectors, quantum processors, quantum sensors that make use of quantum communication for distributed arrays and integrated systems that bring several of these aspects together using Integrated Quantum Photonics. A key need for all of these are technologies with low size, weight and power that can be utilized in aerospace applications.  Some examples of requested innovation include:

• High brightness, efficient and tunable sources of entangled photon pairs.
• Photonic waveguide interferometric circuits for quantum information processing and manipulation of entangled quantum states; requires phase stability, low propagation loss, i.e. < 0.1 dB/cm, and efficient fiber coupling, i.e. coupling loss < 1.5 dB
• Waveguide-integrated single photon detectors for > 100 MHz incidence rate, 1-sigma time resolution of < 25 ps, dark count rate < 100 Hz, and single-photon detection efficiency > 50% at highest incidence rate
• Integrated sensors that support arrays of distributed sensors, such as an entangled interferometric imaging array
• Integrated photonic circuit quantum memory
• Integrated photonic circuits and detectors for balanced homodyne detection
• Quantum entanglement verifying system

Quantum sensor focused proposals that do not include an aspect of quantum communication should propose to the Quantum Sensing and Measurement subtopic as individual quantum sensors are not covered by this subtopic.

References

Katz, Evan, Benjamin Child, Ian Nemitz, Brian Vyhnalek, Tony Roberts, Andrew Hohne, Bertram Floyd, Jonathan Dietz, and John Lekki. “Studies on a Time-Energy Entangled Photon Pair Source and Superconducting Nanowire Single-Photon Detectors for Increased Quantum System Efficiency”, SPIE Photonics West, San Francisco, California, 02/06/2019.

Kitagawa, M. and Ueda, M., “Squeezed spin states," Phys. Rev. A 47, 5138{5143 (1993).

Daniel Gottesman, Thomas Jennewein, and Sarah Croke, “Longer-Baseline Telescopes Using Quantum Repeaters”, Phys. Rev. Lett. 109, 16 August 2012.

Nicolas Gisin & Rob Thew, “Quantum communication”, Nature Photonics volume 1, pages 165–171 (2007)

H. J. Kimble, “The quantum internet”, Nature volume 453, pages 1023–1030 (19 June 2008)

C. L. Degen, F. Reinhard, and P. Cappellaro, “Quantum sensing”, Rev. Mod. Phys. 89, 25 July 2017

Nemitz, Ian, Jonathan Dietz, Evan Katz, Brian Vyhnalek, and Benjamin Child. “Bell inequality experiment for a high brightness time-energy entangled source”, SPIE Photonics West, San Francisco, CA, 03/01/2019.

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Research

Desired Deliverables Description

Phase I research should (highly encouraged) be conducted to demonstrate technical feasibility with preliminary hardware (i.e. beyond architecture approach/theory; a proof-of-concept) being delivered for NASA testing, as well as show a plan toward Phase II integration. Phase II new technology development efforts shall deliver components at the TRL 4-6 level with mature hardware and preliminary integration and testing in an operational environment. Deliverables are desired that substantiate the quantum communication technology utility for positively impacting the NASA mission.  The quantum communication technology should impact one of three key areas: information security, sensor networks, and networks of quantum computers.  Deliverables that substantiate technology efficacy include reports of key experimental demonstrations that show significant capabilities, but in general it is desired that the deliverable include some hardware that shows the demonstrated capability.

State of the Art and Critical Gaps

There is a critical gap between the United States and other countries, such as Japan, Singapore, Austria and China in quantum communications in space.  Quantum communications is called for in the 2018 National Quantum Initiative (NQI) Act, which directs National Institute of Standards and Technology (NIST), National Science Foundation (NSF) and Department of Energy (DOE) to pursue research, development and education activities related to Quantum Information Science. Applications in quantum communication, networking and sensing, all proposed in this subtopic, are the contributions being pursued by NASA to integrate the advancements being made through the NQI.

Relevance / Science Traceability

This technology would benefit NASA communications infrastructure as well as enable new capabilities that support its core missions.  For instance, advances in quantum communication would provide capabilities for added information security for spacecraft assets as well as provide a capability for linking quantum computers on the ground and in orbit. In terms of quantum sensing arrays, there are a number of sensing applications that could be supported through the use of quantum sensing arrays for dramatically improved sensitivity.

Scope Title

Carbon Dioxide Reduction System Components and Unit Processes

Scope Description

NASA has invested in many carbon dioxide reduction technologies over the years to increase the percentage of oxygen recovery from carbon dioxide in human spacecraft for long duration missions. Examples of technologies include, but are not limited to, Series-Bosch, Continuous Bosch, Methane Pyrolysis and Microfluidic Carbon Dioxide Electrolysis. Significant technical challenges still face these process technologies and are impeding progress in technology maturation. Critical technical elements of these technologies have a high degree of technical difficulty. Examples where additional technology development is needed include (this is a partial list):

• High temperature gas purification and/or separation for CO, H₂, and hydrocarbon rich streams.
• Nuisance particulate carbon contamination.
• Solid carbon clogging of frits and filters in recycle gas streams.
• Safe collection, removal and disposal of solid carbon while reactors are in operation.
• Subsystems to recharge reactors with new catalyst and to efficiently use or recycle consumable catalysts.

This subtopic is open to consider novel ideas that address any of the numerous technical challenges that face development of carbon dioxide reduction hardware with particular attention to those listed above. Specifics on two of these challenges are provided below.

Gas Purification and/or Separation for Carbon Monoxide, Hydrogen and Hydrocarbon Rich Streams

Many process technologies currently under development have challenging multi-component streams which could benefit from improved gas separation technology. High purity, high yield and continuous supply of separated gases are all desirable features of a proposed technology. The targeted process streams that may benefit from improved gas separations are the following:

• Producing a high-purity hydrogen product from a hydrogen-rich gas stream containing acetylene (as high as 6.4 mole %), trace amounts of other hydrocarbons (ethylene, ethane, benzene), unreacted methane, carbon monoxide, carbon dioxide and water vapor. It is imperative that the proposed separation technologies do not hydrogenate hydrocarbons, such as acetylene. This separation is directed at methane pyrolysis technologies including the Plasma Pyrolysis Assembly (PPA).
• Hydrogen separation from an ethylene-rich stream. This separation is directed at the effluent stream from a Microfluidic Electrochemical Reactor which consists of ethylene, hydrogen, methane, carbon monoxide, carbon dioxide and water vapor.
• Recovery of unreacted carbon dioxide and hydrogen from a carbon monoxide-rich stream. This separation is needed for a Bosch/Reverse Water Gas Shift (RWGS) Reactor.

Technology solutions could include, but not be limited to, filtration, mechanical separation or novel sorbents. If novel sorbents are developed the proposed technology solution should also address issues with scale-up to kg quantities (difficult for some novel sorbents). Technology solutions proposed in this subtopic could potentially be leveraged for In-Situ Resource Utilization (ISRU) applications.

Separation of Particulate Carbon and Hydrocarbons from Process Gas Streams

Oxygen recovery technology options, including carbon formation reactors and methane pyrolysis reactors almost universally result in particulates in the form of solid carbon or solid hydrocarbons. Mitigation for these particulates will be essential to the success and maintainability of these systems during long duration missions. Techniques and methods leading to compact, regenerable devices for removing, managing and disposing of residual particulate matter within ECLSS process equipment are sought. Separation performance approaching HEPA rating is desired for ultrafine particulate matter with minimal pressure drop. The separator should be capable of operating for hours at high particle loading rates and then employ techniques and methods to restore its capacity back to nearly 100% of its original clean state through in-place and autonomous regeneration or self-cleaning operations using minimal or no consumables (including media-free hydrodynamic separators). The device must minimize crew exposure to accumulated particulate matter and enable easy particulate matter disposal or chemical repurposing.

State of the Art and Critical Gaps

Future long duration human exploration missions may benefit from further closure of the Atmosphere Revitalization System (ARS).  The state-of-the-art Sabatier system, which has flown on the International Space Station as the Carbon Dioxide Reduction Assembly (CRA), only recovers about half of the oxygen from metabolic carbon dioxide. This is because there is insufficient hydrogen to react all available carbon dioxide. The Sabatier reacts hydrogen with carbon dioxide to produce methane and water.  The methane is vented overboard as a waste product causing a net loss of hydrogen. Mars missions target >75% oxygen recovery from carbon dioxide, with a goal to approach 100% recovery. NASA is developing several alternate technologies that have the potential to increase the percentage of oxygen recovery from carbon dioxide, toward fully closing the ARS loop. Methane pyrolysis recovers hydrogen from methane, making additional hydrogen available to react with carbon dioxide. Other technologies under investigation process carbon dioxide, recovering a higher percentage of oxygen than the Sabatier. All of these alternative systems, however, need additional technology investment to reach a level of maturity necessary for consideration for use in a flight environmental control and life support system (ECLSS).

Scope Title

Solid Carbon Repurposing

Scope Description

Solid carbon is produced as a major by-product from many candidate oxygen recovery technologies under consideration for long-duration missions, including Bosch, Series Bosch, Methane Pyrolysis by Carbon Vapor Deposition, and technologies containing carbon formation reactors. Based on metabolic CO₂ production for a crew of 4, 1.135 kg of solid carbon, with a volume as high as 2.8 liters, may be produced each day by oxygen recovery technologies, which then must be disposed of or repurposed. Repurposing of this carbon reduces logistical challenges associated with its disposal and may ultimately result in materials or processes advantageous for long-duration missions. The produced solid carbon may include nanofibers, microfibers and amorphous material with varying particle size, with the smallest in the micrometer range (10-50 µm). It may contain quantities of metals including, but not limited to, iron, nickel and cobalt. The solid carbon may be in the form of a loose powder or a densified cake with densities ranging from 0.4 to 1.8 g/cc and will vary by technology. Venting or disposal of this carbon to space will present considerable logistical challenges and will result in large volumes of space debris. Disposal of this carbon on a planetary surface may result in concerns for planetary protection or planetary science. NASA is seeking technologies and/or processes that repurpose solid carbon and its contaminants resulting in useful products for transit, deep space or planetary surface missions. The technology and/or process must limit crew exposure to the raw carbon.

References for All Scopes

"Hydrogen Recovery by Methane Pyrolysis to Elemental Carbon" (49th International Conference on Environmental Systems, ICES-2019-103)

"Evolving Maturation of the Series-Bosch System" (47th International Conference on Environmental Systems, ICES-2017-219)

"State of NASA Oxygen Recovery" (48th International Conference on Environmental Systems, ICES-2018-48)

"Particulate Filtration from Emissions of a Plasma Pyrolysis Assembly Reactor Using Regenerable Porous Metal Filters" (47th International Conference on Environmental Systems, ICES-2017-174)

"Methane Post-Processing and Hydrogen Separation for Spacecraft Oxygen Loop Closure" (47th International Conference on Environmental Systems, ICES-2017-182)

“Trading Advanced Oxygen Recovery Architectures and Technologies” (48th International Conference on Environmental Systems, ICES-2018-321)

NASA-STD-3001, VOLUME 2, REVISION A, Section 6.4.4.1 “For missions longer than 14 days, the system shall limit the concentration in the cabin atmosphere of particulate matter ranging from 0.5 μm to 10 μm (respirable fraction) in aerodynamic diameter to <1 mg/m3 and 10 μm to 100 μm to <3 mg/m3.”  https://www.nasa.gov/sites/default/files/atoms/files/nasa-std-3001-vol-2a.pdf [128].

Expected TRL or TRL range at completion of the project for Phase I: 3

Expected TRL or TRL range at completion of the project for Phase II for All Scopes:  4 to 5

Desired Deliverables of Phase II for All Scopes

Prototype, Analysis, Hardware, Research

Desired Deliverables Description for All Scopes

Phase I Deliverables - Reports demonstrating proof of concept, test data from proof of concept studies, concepts and designs for Phase II. Phase I tasks should answer critical questions focused on reducing development risk prior to entering Phase II. Conceptual solution in Phase I should look ahead to satisfying the requirement of limiting crew exposure to the raw carbon dust.

Phase II Deliverables - Delivery of technologically mature hardware, including components and subsystems that demonstrate performance over the range of expected spacecraft conditions. Hardware should be evaluated through parametric testing prior to shipment. Reports should include design drawings, safety evaluation, test data and analysis. Prototypes must be full scale unless physical verification in 1-g is not possible. Robustness must be demonstrated with long term operation and with periods of intermittent dormancy. System should incorporate safety margins and design features to provide safe operation upon delivery to a NASA facility.

State of the Art and Critical Gaps

No existing operational technology exists in this focused technical area. A crew of 6 during a 540 day Mars surface mission could potentially generate 920 kg of solid carbon - this will be a significant storage or disposal issue and may be a considerable raw product resource for potential utilization. Very limited research and development have been performed in this area. Some studies added carbon to plastic trash which subsequently was processed by a heat melt compactor to make "tiles", which encapsulated the carbon. Although these tiles are a safe way to get rid of trash waste, they were also studied for potential benefit for use as spacecraft radiation shielding.  Other work included adding binders to make rudimentary bricks for structural use.

Relevance / Science Traceability

These technologies would be essential and enabling to long duration human exploration missions, in cases where closure of the atmosphere revitalization loop will trade over alternate ECLSS architectures. The atmosphere revitalization loop on the ISS is only about 50% closed when the Sabatier is operational. These technologies may be applicable to Gateway, Lunar surface, and Mars, including surface and transit. This technology could be proven on the ISS.

This subtopic is directed at needs identified by the Life Support Systems Capability Leadership Team (CLT) in areas of water recovery and environmental monitoring, functional areas of Environmental Control and Life Support Systems (ECLSS).

The Life Support Systems (LSS) Project, under the Advanced Exploration Systems (AES) Program, within the Human Exploration and Operations Mission Directorate (HEOMD), is the expected customer. The LSS Project would be in position to sponsor Phase III and technology infusion.

Scope Title

Spacecraft Microbial Monitoring for Long Duration Human Missions

Scope Description

With the advent of molecular methods, emphasis is now being placed on nucleic acids to rapidly detect microorganisms. However, the sensitivity of current gene-based microbial detection systems is low (~100 gene copies per reaction), requires elaborate sample processing steps, involves destructive analyses, and requires fluids to be transferred and detection systems are relatively large size. Recent advancements in the metabolomics field have potential to substitute (or augment) current gene-based microbial detection technologies that are multi-stepped, destructive and labor intensive (e.g. significant crew time). NASA is soliciting non-gene based microbial detection technologies and systems that target microbial metabolites and that quantify the microbial burden of surfaces, air and water inside future long-duration deep space habitats.

Potable Water:
A simple integrated, microbial sensor system that enables sample collection, processing and detection of microbes or microbial activity in the crew potable water supply is sought. A system that is fully-automated and can be in-line in an Environmental Control and Life Support Systems (ECLSS)-like water system is preferred.

Habitat Surfaces:
Future crewed habitats in cis-lunar space will be crew-tended and thus unoccupied for many months at a time. When crew reoccupies the habitat they will want to quickly, efficiently, and accurately assess the microbial status of the habitat surfaces. A microbial assessment / monitoring system or hand-held device that requires little to no consumables is sought.

Airborne Contamination:
Future human spacecraft, such as Gateway and Mars vehicles, may be required to be dormant while crew is absent from the vehicle, for periods that could last from 1 to 3 years. Before crews can return, these environments must be verified prior to crew return. These novel methods have the potential to enable remote autonomous microbial monitoring that does not require manual sample collection, preparation or processing.

References

A list of targeted contaminants for environmental monitoring can be found at "Spacecraft Water Exposure Guidelines for Selected Waterborne Contaminants" located at: https://www.nasa.gov/feature/exposure-guidelines-smacs-swegs [130]

Advanced Exploration Systems Program, Life Support Systems Project:  https://www.nasa.gov/content/life-support-systems [131]

NASA Environmental Control and Life Support Technology Development and Maturation for Exploration: 2018 to 2019 Overview", 49th International Conference on Environmental Systems, ICES-2019-297

https://ttu-ir.tdl.org/bitstream/handle/2346/84496/ICES-2019-297.pdf [132]

National Aeronautics and Space Administration, NASA Technology Roadmaps, TA 6: Human Health, Life Support, and Habitation Systems (National Aeronautics and Space Administration, Draft, May 2015, https://www.nasa.gov/sites/default/files/atoms/files/2015_nasa_technology_roadmaps_ta_6_human_health_life_support_habitation.pdf [133]

NASA Standard 3001 - Requirements:  https://www.nasa.gov/hhp/standards [134]

Expected TRL or TRL range at completion of the project for Phase I: 3

Expected TRL or TRL range at completion of the project for Phase II:  4 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Research

Desired Deliverables Description

Phase I Deliverables - Reports demonstrating proof of concept, test data from proof of concept studies, concepts and designs for Phase II. Phase I tasks should answer critical questions focused on reducing development risk prior to entering Phase II.

Phase II Deliverables - Delivery of technologically mature hardware, including components and subsystems that demonstrate performance over the range of expected spacecraft conditions. Hardware should be evaluated through parametric testing prior to shipment. Reports should include design drawings, safety evaluation, test data and analysis. Prototypes must be full scale unless physical verification in 1-g is not possible. Robustness must be demonstrated with long term operation and with periods of intermittent dormancy. System should incorporate safety margins and design features to provide safe operation upon delivery to a NASA facility.

State of the Art and Critical Gaps

The State of the Art (SOA) on ISS for microbial monitoring is culturing and counting, as well as grab samples which are returned to earth. NASA has invested DNA-based (PCR) systems, partially robotic in some cases, to eliminate the need for on-orbit culturing. However, a fully automated system is still not ready and there is still a gap for a low- or no-crew time detection system.

Relevance / Science Traceability

The technologies requested could be proven on the ISS and would be useful to long duration human exploration missions away from earth, where sample return was not possible.  The technologies are applicable to Gateway, Lunar surface, and Mars, including surface and transit. This subtopic is directed at needs identified by the Life Support Systems Capability Leadership Team (CLT) in areas of water recovery and environmental monitoring, functional areas of Environmental Control and Life Support Systems (ECLSS).  The Life Support Systems (LSS) Project, under the Advanced Exploration Systems Program, Human Exploration and Operations Mission Directorate (HEOMD), is the expected customer. The LSS Project would be in position to sponsor Phase III and technology infusion. The ISS Program will have interest in successful awards for potential flight demonstrations.

As the design for the new Exploration Extra-vehicular Mobility Unit (xEMU) is developed, there are obvious gaps in technologies, which need to be fulfilled to meet the new exploration requirements. Various Exploration Portable Life Support System (xPLSS) Hatch components are at a stall in technology development and require new innovative ideas. These xPLSS Hatch Components (through three scopes) are the focus areas for this solicitation in an attempt to integrate new technologies into the xPLSS.  NASA has plans to go to the moon and as the mission extends further out of Lower Earth Orbit, durability and extensibility will become some of the most important requirements.

This subtopic is relevant to the Exploration Extravehicular Mobility Unit (xEMU), ISS, as well as commercial space companies. As a new Space Suit Exploration Portable Life Support System (xPLSS) is being designed, built, integrated and tested at JSC and integrated into the xEMU, solutions will have a direct infusion path as the xPLSS is matured to meet the design and performance goals.

Scope Title

Feedwater Supply Assembly

Scope Description

Sterile compliant bladder, capable of storing ultrapure feedwater with a relatively high cycle life:In order for the thermal control loop to operate properly, a water source is needed. An effective, efficient, sterile and durable feedwater bladder is essential. The suit pressure acts on this bladder and as water evaporates, the bladder resupplies the loop. The bladder must be clean and not leak particulates or polymer chains over long periods of quiescence. The water in the control loop contains a biocide and the bladder must not react with these chemicals to form potential contaminants. The maximum design pressure (MDP) for the system at a lunar environment will be 16 psid with a cycle life of 4 X 156 = 624 MDP. Having a bladder with these qualities not only buys down the safety risk of rupture, it promotes reliability at higher pressures and provides an avenue to extend Extravehicular Activity (EVA) length.

References

Feedwater Supply Assembly Requirements

Note to vendor: The following two drawings referenced in the above specification shall be provided if vendor is selected for award.

1. Feedwater Supply Assembly (FSA 431) Drawing SLN 13102397 
   

   https://ntrs.nasa.gov/search.jsp?R=20190033446 [136]

2. Auxiliary Feedwater Supply Assembly (FSA 531) Drawing SLN 13102398 
   

   https://ntrs.nasa.gov/search.jsp?R=20190033446 [136]

Scope Title

Bypass Relief Valve

Scope Description

Material dependent Relief Valve (RV) capable of re-calibration: The bypass relief valve cracks and flows from the pump outlet to the pump inlet, short-circuiting the pump when there is a blockage in the line. It is a safety feature designed to limit the head pressure that could be generated by the positive displacement pump, which is used in the primary and auxiliary thermal control loops. Materials, design pressures and re-calibration capabilities are a priority for this design. The desired housing material is titanium, which is a difficult metal to work with, but is a requirement as a preventative measure to avoid galvanic coupling between interfacing metals. To ensure the thermal loop pressure stays within a safe range, the crack and reseat pressures must be between 14-15 psid with a full flow of 220 lb/hr at <18 psid. The design should also include a method of setting or re-calibrating the cracking pressure in case there is drift over time. Replacement of the entire unit is not preferred due to accessibility and operational concerns.

References

Thermal Loop Bypass Relief Valve Requirements

Note to vendor: The following drawing referenced in the above specification shall be provided if vendor is selected for award.

• Bypass Relief Valve Assembly (RV-424/RV-524) SLN13102925
  

  https://ntrs.nasa.gov/search.jsp?R=20190033446 [136]

Scope Title

Trace Contaminant Control

Scope Description

Trace contaminant removal capability:  Non-regenerable activated carbon is the current state of the art for trace contamination control.  However, this provides a logistics impact to future missions. The primary trace contaminants that must be removed include ammonia (NH₃), carbon monoxide (CO), formaldehyde (CH₂O), and methanethiol (also known as methyl mercaptan) (CH₃SH). The minimum objective would be to remove all of the significant compounds that threaten to exceed the 7-day Spacecraft Maximum Allowable Concentrations (SMAC) values during an EVA. The ideal solution would be a vacuum-regenerable sorbent that could be integrated with the Exploration Portable Life Support System (xPLSS) CO₂/H₂O removal system. This system performs regeneration or desorption by exposing the sorbent to a pressure swing from 4.3 psia to <1 torr over approximately 2 minutes. Temperatures remain in the 60-80^oF range with a small amount of heat flux from the cross-coupled adsorbing bed. Additional heat input requirements from resistance heaters or other sources would negatively impact the system trade the more significant the value becomes.

References

Trace Contamination Control Cartridge Requirements

Note to vendor: The following drawing referenced in the above specification shall be provided if vendor is selected for award.

• Trace Contamination Control (TCC-360) Specification Control Drawing SLN13102266 
  

  https://ntrs.nasa.gov/search.jsp?R=20190033446 [136]

Expected TRL or TRL range at completion of the project for all scopes: 3 to 5

Desired Deliverables of Phase II for all scopes

Prototype

Desired Deliverables Description for all scopes

Phase I products:  By the end of Phase I, it would be beneficial to have a concept design for infusion into the Exploration Portable Life Support System (xPLSS). Testing of the concept is desired at this Phase.

Phase II products:  By the end of Phase II, a prototype ready for system-level testing in the xPLSS or in a representative loop of the PLSS is desired.

State of the Art and Critical Gaps

As the design for the new Exploration Extra-vehicular Mobility Unit (xEMU) is developed, there are obvious gaps in technologies, which need to be fulfilled to meet the new exploration requirements. Various Exploration Portable Life Support System (xPLSS) Hatch components are at a stall in technology development and require new innovative ideas. These xPLSS Hatch Components are the focus areas for this solicitation in an attempt to integrate new technologies into the xPLSS. NASA has plans to go to the moon and as the mission extends further out of Lower Earth Orbit, durability and extensibility will become some of the most important requirements.

Relevance / Science Traceability

It is relevant to the Exploration Extravehicular Mobility Unit (xEMU), ISS, as well as commercial space companies. As a new Space Suit Exploration Portable Life Support System (xPLSS) is being designed, built, integrated, and testing at JSC and integrated into the xEMU, solutions will have a direct infusion path as the xPLSS is matured in to meet the design and performance goals.

Scope Title

Liquid Cooling and Ventilation Garment (LCVG) water loop connector upgrade and glove humidity reduction

Scope Description

LCVG water connector upgrade:The connector of the liquid cooling and ventilation garment (LCVG) for the space suit has been a source of failures in the current extra-vehicular mobility unit (EMU). Increased reliability and durability are needed for future space suits that will be used during long-duration missions, which include periods (up to 6 months) of quiescence. Two primary design problems can be addressed:

1)     Cold flow of the ethyl-vinyl acetate tubing at the connection to the LCVG connector, which causes leaks to form

2)     Sticking of the poppet seal, which allows the LCVG connector to leak. The poppet seal sticks after the seal lubricant is washed away.

A requirement that increases the challenge in designing a non-sticking poppet seal is, because the poppet seal is in the water loop of the space suit, the seal material used must maintain the high water quality requirements for the space suit water loop. Water leakage from the LCVG thermal loop connectors shall be less than 0.5 cc/hr when running at nominal operating pressure of 15 psid.

The connector should not generally leach material into the water flowing through it. Therefore, the connector needs to maintain water quality to the following levels in order to avoid affecting the performance of other equipment within the space suit water loop. In addition, galvanic corrosion in the water loop is of concern. Therefore the connector wetted surfaces, and in general the body should be constructed out of Titanium 6Al-4V wherever possible and stainless steel when necessary. Aluminum alloys should be avoided. Other wetted materials, such as seals or gaskets would preferably be constructed out of currently-used materials such as silicones.

The connector would also need to be compatible with the water solution of Iodine at concentrations of 0.5 – 5 ppm.

Additionally, the connector would need to be compatible with inlet water containing contaminants such as those listed below:

Contaminant         Amount (mg/L)

Barium                                     0.1

Calcium                                    1

Chlorine                                   5

Chromium                               0.05

Copper                                     0.5

Iron                                           0.2

Lead                                         0.05

Magnesium                            1

Manganese                             0.05

Nickel                                       0.05

Nitrate                                     1

Potassium                               5

Sulfate                                     5

Zinc                                          0.5

Organics

Total Acids                              0.5

Total Alcohols                        0.5

Total Organic Carbon           0.3

Glove humidity reduction:  Onycholysis due to humidity and water in space suit gloves during Neutral Buoyancy Laboratory (NBL) training and during extra-vehicular activity is a common observation. Ventilation in gloves is poor allowing moisture to accumulate, which contributes to onycholysis and results in nail bed damage, skin damage, and fungal infections. NASA seeks solutions to reducing moisture in space suit gloves. LCVG ventilation improvements that could ventilate the glove are difficult due to ducting required that would cross the elbow. This ducting is undesirable since it impedes mobility of the elbow joint. Alternative solutions are desired that will prevent onycholysis during suited operations.

The LCVG ventilation ducting consists of a ducting network with one duct running down each arm and each leg. See “Liquid Cooling and Ventilation Garment” description and images at “https://www.nasa.gov/audience/foreducators/spacesuits/home/clickable_suit_nf.html [138]. The ventilation ducts end just above the elbows for the arms and at the feet for the legs. The ventilation gas enters the spacesuit at helmet and flows over the body because the ends of the ducts at the elbows and feet are open. The fan in the portable life support subsystem (PLSS) pulls the ventilation from these open ends and sends the gas to be processed before recycling it back to the helmet. Since the ventilation duct in the arms end at the elbows, the wrist and hand areas are not well ventilated.  

References

“Liquid Cooling and Ventilation Garment” description and images located at the following link:  https://www.nasa.gov/audience/foreducators/spacesuits/home/clickable_suit_nf.html [138].

A high-level schematic of the LCVG connector https://www.nasa.gov/suitup/reference/catalog [139]

Expected TRL or TRL range at completion of the project: 2 to 5

Desired Deliverables of Phase II

Hardware, Research

Desired Deliverables Description

The phase 1 needs to deliver a detailed design solution with information that provides confidence that hardware fabricated in the Phase II will resolve the current design challenges.

State of the Art and Critical Gaps

The 30+ history of the EMU has demonstrated these two design weaknesses as a potential for space suit failures for the exploration space suit. Without new design solutions, the exploration space suit will be limited by these weaknesses. In preparation for the exploration space suit, solving these problems are critical. 

Relevance / Science Traceability

This subtopic is relevant across the Moon to Mars portfolio. Any mission in which an extra-vehicular activity suit is utilized will benefit from the increased reliability of a suit in which the current connector flaws are rectified.

Scope Title

Model Based Systems Engineering for Distributed Development

Scope Description

Systems Engineering technology is both a critical capability and a bottleneck for NASA human exploration development. NASA looks to a sustainable return to the Moon to enable future exploration of Mars, components such as Lunar Gateway and Commercial Lunar Payload Services (CLPS) will require partnerships with a wide variety of communities. Building from the success of the international partnerships for International Space Station (ISS), space agencies from multiple governments are looking for roles on the Gateway. A particular focus has been made to include the rapidly growing commercial space industry to provide an important role in supporting a sustained presence on the Moon. All of these potential partners will have their own design capabilities, their own development processes and internal constituencies to support. Integrating and enabling disparate systems built in different locations by different owners to all work cohesively together will require a significant upgrade to the core systems engineering capabilities.

In the last decade Model-Based Systems Engineering (MBSE) technology has matured as evidenced by the development of Systems Modeling Language (SysML) tools and frameworks that support engineers in development efforts from requirements through hardware and software implementation. MBSE holds considerable promise for accelerating, reducing overhead labor, and improving the quality of systems development. However, a remaining bottleneck is the coordination and integration of system development across distributed organizations, such as the multiple partners developing lunar gateway and eventual Mars exploration. This subtopic seeks technology to fill this gap.

Areas of particular need include:

• Methodologies that support integration among tools and exchange of information between multidisciplinary artifacts using automated intelligent reasoning.
• The definition of open interface standards and tools to enable inspection of distributed models across engineering domains.
• Tools or systems that allow models to be shared across development environments and trace the resulting system model back to contributions from multiple partners.
• Modeling environments that facilitate user interaction from multiple stakeholders of varying expertise in MBSE.
• Continuous integration and verification of safety critical system requirements that depend on disparate development sources.

References:

• https://www.nasa.gov/consortium/ModelBasedSystems [141]
• http://www.omgsysml.org [142]
• Ensuring information exchange of digital artifacts are transferable and up to date among multiple stakeholders.
  • Digital Engineering Information Exchange Working Group (DEIX WG): http://www.omgwiki.org/MBSE/doku.php?id=mbse:deix [143]
• Computational tools to augment human decision making and reasoning on complex systems with large amounts of data from disparate sources
  • Augmented Intelligence for Systems Engineering challenge team (AI-SECT): http://www.omgwiki.org/MBSE/doku.php?id=mbse:augmented [144]
• Automated formal specification, formal verification, and test case generation of requirements with linked data and traceability to discipline specific (CAD, CAE, etc.) tools, particularly requirements with safety properties.
  • ReqIF: https://www.omg.org/reqif/ [145]
  • SysPhs: https://www.omg.org/spec/SysPhS/ [146]
  • FMI: https://fmi-standard.org [147] 
• Lightweight and intuitive cloud-based interfaces for CRUD (create, read, update, delete) operations on models particularly for users with limited MBSE experience.
• Open-MBEE: https://openmbee.org [148]
• OSLC: https://open-services.net/ [149]

Expected TRL or TRL range at completion of the project: 4 to 6

Desired Deliverables of Phase II

Prototype, Software

Desired Deliverables Description

Methodologies and tools that support distributed development efforts

State of the Art and Critical Gaps

For distributed development, the state-of-the-art tends to be laboriously negotiated interface control documents and manual integration processes that are inherently slow and labor intensive. In an effort to overcome these challenges MBSE and SysML in particular has seen significant adoption at NASA (Gateway, Resource Prospector, Europa Clipper, Space Communications and Navigation [SCaN], Space Launch System [SLS]) especially after the MBSE Pathfinder ('16/'17) and MBSE Infusion And Modernization Initiative (MIAMI, '18/'19) studies. However, these pilot programs and a survey of NASA's use of MBSE conducted by NASA Independent Verification & Validation (IV&V) and Ames Research Center identified areas of critical need, including:

1. Sharing and version control of models.
2. Integration of SysML of domain specific tools
3. Steep learning curve for users with limited MBSE experience
4. Testing, Verification and Validation with SysML have limited use
5. No tools exist for formally specifying requirements and linking to model properties

With programs such as Gateway and Artemis that require coordination among multiple NASA centers, international space agencies, and commercial partnerships these needs will be amplified.   Tool infrastructures that enable integrated support of requirements tracing, design reference points, intelligent reasoning of data and interface constructs are generally not available except within proprietary boundaries. We need tools that support integrated development and model sharing across development environments and that support use across multiple vendors.

Relevance / Science Traceability

This subtopic would be of relevance to all Human Exploration and Operations Mission Directorate (HEOMD) missions, but of particular interest will be Gateway and Artemis development. Those systems have already adopted the use of MBSE tools and tools sought help reduce potential system integration bottlenecks. Over the next 3 to 5 years, there will be considerable opportunity for small business contributions to be matured and integrated into the support infrastructure as Gateway evolves from concept to development program.

Scope Description

The use of commercial off-the-shelf (COTS) parts in space for electronics is a potential significant enabler for many capabilities during a mission. This subtopic is seeking a better understanding of the feasibility of COTS electronics in space environments. It seeks strategies based on a complete system analysis that include, but not limited only to, failure modes to mitigate radiation induced impacts to systems in the space radiation environment.

As background, spacecraft experience exposure to damaging radiation and that amount of exposure from various sources, (e.g., sun and galactic cosmic radiation sources) increases notably as the spacecraft ventures further away from the Earth’s magnetic field, since the magnetic field offers some level of protection. As spacecraft, and their electronic systems, proceed again to the moon and further into deep space, considerable work has and continues to be done to evaluate and determine how to appropriately protect the astronauts and to shield or otherwise protect various spacecraft, habitats, and their electronic systems, depending upon the needs of the missions.

Many of the most protective physical shielding approaches known result in infrastructure which is too heavy for what is considered acceptable for many missions’ intended launch and spaceflight conditions. Therefore, typically lighter infrastructure shielding is presently being used when and where possible. Spacecraft faring deeper into space for fly-by missions (e.g., New Horizons), orbiters (e.g., Mars Orbiter), or landers (e.g., Mars Rover) are examples of such relatively lightly shielded systems. The lighter shielding sacrifices some radiation protection and therefore results in some limitations in what their electronic systems could do. There are already ongoing projects to upgrade current radiation hardened parts, but these are not COTS items and are expensive to manufacture and to buy. For critical systems that must be operational continuously and which may also have more lightly shielded systems, there is no other option at this time. This subtopic does not seek work of that nature.

Unlike the lightly shielded space environments discussed above, space environments which are highly shielded from radiation, such as is inherently the case for the interiors of manned missions and for habitats where humans live and work, high level radiation hardened systems may not be as necessary even in deeper space beyond most of the present day low earth orbit (LEO) situations. Instead, a less expensive COTS solution may be acceptable for a number of non-critical tasks that are not harmed by power interruptions, hardware failures, radiation upsets, etc. in those environments over what may have been thought likely. In order to assess the feasibility of a COTS solution for those types of highly shielded space environments, this subtopic is seeking proposals.

Successful Small Business Concern/Research Institution teams would be able to do space radiation modeling and a complete analysis of the COTS (e.g., modelling for an appropriate space relevant environment; statistical modeling of the electronic parts themselves and their connections in a system; destructive testing and analysis; and testing in an appropriate space relevant environment [e.g., in particle beams]). Further, since all parts in these systems cannot be individually tested, an understanding of what parts are susceptible to radiation damage is crucial so as to create the list of potential test candidates.

Phase I proposers are expected to develop a plan or strategy that explains and details how they would approach solving the problem that helps NASA mitigate radiation induced failures in the system/components, identify COTS equipment that are likely candidates based on environmentally relevant testing, as well as modeling of interior environment and data analysis of similarly known/used approaches like the Orion vehicle testing (EM-1 when released). They should highlight the innovation in the suggested approach and explain why it would be a better solution over what may presently be used. Additionally, they should also indicate how the proposed strategies could be used commercially if developed. Phase I concept studies are expected raise the TRL to at least a 3/4 when completed. Phase II proposals would use that innovative approach to refine and conduct further relevant interior environmental modeling and conduct the space radiation relevant testing and analysis on the selected COTS parts/systems which could lead toward creating prototypes of the potential commercial items that come from the analysis. The deliverables from a successful Phase II is expected to raise the TRL to 5/6.

References

There are many references on each individual aspect of the work involved, but very few references on the entire process wanted. For a tool that can model the radiation environment inside a spacecraft:

OLTARIS: On-line Tool for the Assessment of Radiation in Space, NASA/TP-2010-216722, July 2010. R.C.Singleterry, S.R.Blattnig, M.S.Clowdsley, G.D.Qualls, C.A.Sandridge, L.C.Simonsen, J.W.Norbury, T.C.Slaba, S.A.Walker, F.F.Badavi, J.L.Spangler, A.R.Aumann, E.N.Zapp, R.D.Rutledge, K.T.Lee, R.B.Norman.

A reference to help understand the radiation testing of powered COTS parts, see:

Correlation of Neutron Dosimetry Using a Silicon Equivalent Proportional Counter Microdosimeter and SRAM SEU Cross Sections for Eight Energy Spectra, IEEE Transaction on Nuclear Science, Vol.~50, No.~6, pp.~2363-2366, December 2003. B.Gersey, R.Wilkins, H.Huff, R.C.Dwivedi, B.Takala, J.O'Donnell, S.A.Wender, R.C.Singleterry

Expected TRL or TRL range at completion of the project:  3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Software, Hardware, Research

Desired Deliverables Description

Either a prototype or flyable hardware to perform the proposed task.  Either software or software reports that show theoretically, the hardware will withstand the space environment with any predictions of failure rates or potential upset rates and mitigation.

State of the Art and Critical Gaps

Many systems have never been subjected to replacement with COTS part based systems, either off the shelf systems or specialty designed systems with COTS parts.  The list is long and not appropriate for NASA to designate a list.  It is up to the proposer to identify what has been done in the past to mitigate COTS parts in a system, if anything.

Relevance / Science Traceability

This work would benefit all entities flying specialty systems in space.  If reduced cost, more reliable and capable systems are needed, then COTS is a pathway to this.  It just needs to be confirmed that the system can survive in the space environment.

Scope Title

Nanotechnology Innovations for Spacecraft Water Management Applications

Scope Description

Water recovery from wastewater sources is key to long duration human exploration missions. Without substantial water recovery, life support system launch weights are prohibitively large. Regenerative systems are utilized on the International Space Station (ISS) to recycle water from humidity condensate and urine. The Water Processor Assembly (WPA) accepts distillate from the Urine Processor Assembly (UPA) and humidity condensate from condensing heat exchanges. The WPA contains multi-filtration beds to remove inorganic and non-volatile organic contaminants, followed by a catalytic oxidation reactor where low molecular weight organics not removed by the adsorption process are oxidized in the presence of oxygen, elevated temperature, and a catalyst. To stabilize urine and protect components from biofouling and precipitation, a toxic pretreatment formula is added to collected urine. Simple measurements of water composition are made during flight, including conductivity, total organic carbon and iodine concentration. For determination of ionic or organic species in water and wastewater, samples must be returned to earth.

This subtopic solicits for technologies to fill specific gaps in NASA’s water management systems for human spaceflight. Proposals must address needs in one of the three target areas specified. These areas of scope are aligned with the three specific thrusts described within the white paper of the Nanotechnology Signature Initiative (NSI) "Water Sustainability through Nanotechnology". Please see references for additional information, including water quality requirements and guidelines.

Increasing Water Availability Using Nanotechnology:  Removal of Problematic Contaminants from Processed Wastewater

Two problematic organic compounds are recalcitrant to WPA processing on the ISS. Dimethylsilanediol (DMSD) is a silicon-containing degradation byproduct from siloxane based compounds. DMSD can violate ISS potable water quality standards over time, requiring premature multifiltration (MF) bed replacement. Dimethyl sulfone (DMSO2) is a sulfur-containing metabolic byproduct that has historically been consistently present in ISS potable water delivered to the Oxygen Generation Assembly (OGA) for electrolysis to O₂ and H₂. DMSO2 accumulates in the OGA water recirculation loop and is thus present in the OGA hydrogen product stream. When fed to the Sabatier reactor this contaminated H₂ has been shown to poison the Sabatier catalyst over time from sulfur exposure. The presence of DMSO2 is negatively impacting exploration design requirements and Concepts of Operation (CONOPS) for the Advanced-OGA and the Sabatier subsystems, including periodic automated flushing and trace contaminant getter devices. The development of a technology or method for physicochemical removal of these contaminants, compatible with the ISS WRS/WPA, will benefit both current manned and future exploration missions. Although technical solutions are sought that involve novel utilization of nanotechnology, proposals using more conventional or alternative approaches will also be considered.

Improving the Efficiency of Water Delivery and Use with Nanotechnology:  Management and Monitoring of Silver Biocide in Potable Water

NASA is considering using silver as the active biocide in potable water systems for use in future spacecraft. NASA is seeking technologies for delivery, maintenance and monitoring silver in potable water.

• NASA seeks technologies to deliver and replenish silver ions in potable water, to maintain a concentration at a chosen set point within a range of 200 to 400 ug/L. The system should be capable of operating in-line, to deliver silver at a flow rate of 0.1 to 0.15 L/min potable water. Furthermore, the device should be able to operate at ambient temperature, pH ranges between 4.5 - 9.0, and system pressures up to 30 psig (200 kPa). Moreover, the device should also be small, robust, lightweight, and have minimal power and consumable mass requirements. Additionally, candidate technologies should be microgravity compatible and have no adverse effects on the potability of the drinking water system. The technology should also be capable of providing continuous, stable and autonomous operation, and be fully functional following periods of long-term system dormancy – up to 1 year.
• Silver ions may drop out of solution, depositing on fluid lines and tank surfaces, resulting in loss of silver concentration, impacting its efficacy as a residual disinfectant in potable water. Alternative methods are sought to minimize loss of silver ions in spacecraft potable water plumbing systems.
• NASA is interested in sensing technologies for the in-line measurement of ionic silver in spacecraft potable water systems. Overall, the sensing technology should offer small, robust, lightweight, low-power, compatible design solutions capable of stable, continuous, and autonomous measurements of silver for extended periods of time. Sensors of particular interest would provide:  continuous in-line measurement of ionic silver at concentrations between 0 and, at least, 1000 parts per billion (ppb); a minimum detection limit of 10 ppb or less; measurement accuracy of at least 2.5% full scale (1000 ppb); stable measurements in flows up to 0.5 L/min and pipe diameters up to ¾ inch; high sampling frequency, e.g., up to 1 measurement per minute; stable calibration, greater than 3 years preferred; minimal and/or no maintenance requirements; operation at ambient temperature, system pressures up to 30 psig (200 kPa), and a solution pH between 4.5 - 9.0; and finally, a volumetric footprint less than 2000 cubic centimeters. The sensing technology should have little to no impact on the overall volume and concentration of silver being maintained within the spacecraft water system.

Enabling Next-Generation Water Monitoring Systems with Nanotechnology

NASA is seeking miniature analytical systems to measure mineral and organic constituents in potable water and wastewater. NASA is interested in sensor suites capable of simultaneous measurement of inorganic and organic species. Spacecraft applications exist for monitoring species within wastewater (potential waste streams:  urine, humidity condensate, Sabatier product water, waste hygiene, and waste laundry water), regenerated potable water and in support of on-board science. Multi-species analyte measurement capability is of interest that would be competitive to standard water monitoring instruments such as ion-chromatography, inductively coupled plasma spectroscopy, and high performance liquid chromatography. Components that enable the miniaturization of these monitoring systems, such as microfluidics and small scale detectors, will be considered. Technologies should be targeted to have >3 year service life and >50% size reduction compared to current state of the art. Ideally, monitoring systems should require no hazardous reagents, have long-term calibration stability, and require very little crew time to operate and maintain.

References

NASA is a collaborating agency with the NTSC Committee on Technology Subcommittee on Nanoscale Science, Engineering and Technology's Nanotechnology Signature Initiative (NSI): "Water Sustainability through Nanotechnology" (Water NSI). For a white paper on the NSI, see https://www.nano.gov/node/1580 [152]

A high-level overview of NASA's spacecraft water management was presented at a webinar sponsored by the Water NSI: "Water Sustainability through Nanotechnology: A Federal Perspective, Oct. 19, 2016" https://www.nano.gov/publicwebinars [153]

A general overview of the state of the art of spacecraft water monitoring and technology needs was presented at a webinar sponsored by the Water NSI: "Water Sustainability through Nanotechnology: Enabling Next-Generation Water Monitoring Systems, Jan. 18, 2017" located at https://www.nano.gov/publicwebinars [153]

For a list of targeted contaminants and constituents for water monitoring, see "Spacecraft Water Exposure Guidelines for Selected Waterborne Contaminants" located at https://www.nasa.gov/feature/exposure-guidelines-smacs-swegs [130]

Advanced Exploration Systems Program, Life Support Systems Project https://www.nasa.gov/content/life-support-systems [131]

National Aeronautics and Space Administration, NASA Technology Roadmaps, TA 6: Human Health, Life Support, and Habitation Systems (National Aeronautics and Space Administration, Draft, May 2015, www.nasa.gov/sites/default/files/atoms/files/2015_nasa_technology_roadmaps_ta_6_human_health_ life_support_habitation.pdf [154]).

Layne Carter, Jill Williamson, Daniel Gazda, Chris Brown, Ryan Schaezler, Frank Thomas, Jesse Bazley, Sunday Molina “Status of ISS Water Management and Recovery” 49th International Conference on Environmental Systems, ICES-2019-36 https://ttu-ir.tdl.org/bitstream/handle/2346/84720/ICES-2019-36.pdf [155]

Dean L. Muirhead, Layne Carter “Dimethylsilanediol (DMSD) Source Assessment and Mitigation on ISS: Estimated Contributions from Personal Hygiene Products Containing Volatile Methyl Siloxanes (VMS)” 48th International Conference on Environmental Systems, ICES-2018-123. https://ttu-ir.tdl.org/bitstream/handle/2346/74112/ICES_2018_123.pdf [156]

Chad Morrison, Christopher McPhail, Mike Callahan, Stuart Pensinger “Concepts for a Total Organic Carbon Analyzer for Exploration Missions” 49th International Conference on Environmental Systems, ICES-2018-254 https://ttu-ir.tdl.org/bitstream/handle/2346/84465/ICES-2019-254.pdf [157]

Molly S. Anderson, Ariel V. Macatangay, Melissa K. McKinley, Miriam J. Sargusingh, Laura A. Shaw, Jay L. Perry, Walter F. Schneider, Nikzad Toomarian, Robyn L. Gatens " NASA Environmental Control and Life Support Technology Development and Maturation for Exploration: 2018 to 2019 Overview", 49th International Conference on Environmental Systems, ICES-2019-297 https://ttu-ir.tdl.org/bitstream/handle/2346/84496/ICES-2019-297.pdf [132]

Donald Layne Carter, David Tabb, Molly Anderson "Water Recovery System Architecture and Operational Concepts to Accommodate Dormancy", 47th International Conference on Environmental Systems, Paper ICES-2017-43 https://ttu-ir.tdl.org/ttu-ir/bitstream/handle/2346/72884/ICES_2017_43.pdf [158]

Li, Wenyan, Calle, Luz, Hanford, Anthony, Stambaugh, Imelda and Callahan, Michael "Investigation of Silver Biocide as a Disinfection Technology for Spacecraft – An Early Literature Review", 48th International Conference on Environmental Systems, Paper ICES-2018-82

Expected TRL or TRL range at completion of the project for Phase I:  3

Expected TRL or TRL range at completion of the project for Phase II:  4 to 5

Desired Deliverables of Phase II:

Research, Analysis, Prototype, Hardware

Desired Deliverables Description

Phase I Deliverables - Reports demonstrating proof of concept, including test data from proof of concept studies, and concepts and designs for Phase II. Phase I tasks should answer critical questions focused on reducing development risk prior to entering Phase II.

Phase II Deliverables - Delivery of technologically mature hardware, including components and subsystems that demonstrate performance over the range of expected spacecraft conditions. Hardware should be evaluated through parametric testing prior to shipment. Reports should include design drawings, safety evaluation, test data and analysis. Prototypes must be full scale unless physical verification in 1-g is not possible. Robustness must be demonstrated with long term operation and with periods of intermittent dormancy. System should incorporate safety margins and design features to provide safe operation upon delivery to a NASA facility.

State of the Art and Critical Gaps

NASA has unique water needs in space that have analogous applications on Earth. NASA’s wastewater collection differs from systems used on Earth in that it is highly concentrated with respect to urine, uses minimal flush water, is separated from solid wastes, and contains highly acidic and toxic pretreatment chemicals. NASA is interested in recovery of potable water from waste water, low toxicity residual disinfection, antifouling treatments for plumbing lines and tanks, "microbial check valves" that prevent microbial cross-contamination where water treatment and potable water systems share connections, and miniaturized sensors and monitoring systems for contaminants in potable water and waste water. NASA’s goal is zero-discharge water treatment, targeting 100% water recycling and reuse. Spacecraft traveling away from Earth require the capability of a fully functional water analysis laboratory, including identification and quantification of known and unknown inorganic ions, organics, and microbes, as well as pH, conductivity, total organic carbon and other typical measurements. Spacecraft Water Exposure Guidelines (SWEGs) have been published for selected contaminants. Nanotechnology may offer solutions in all of these application areas.

Relevance / Science Traceability

This technology could be proven on the ISS and would be useful to long duration human exploration missions, including Gateway, Lunar surface, and Mars, including surface and transit.  It is essential and enabling for water to be recycled to reduce launch costs associated with life support consumables. This subtopic is directed at needs identified by the Life Support Systems Capability Leadership Team (CLT) in areas of water recovery and environmental monitoring, functional areas of Environmental Control and Life Support Systems (ECLSS).

This subtopic is directed at meeting NASA's commitments as a collaborating agency in the National Nanotechnology Signature Initiative: "Water Sustainability through Nanotechnology". This initiative was established under the NTSC Committee on Technology, Subcommittee on Nanoscale Science, Engineering and Technology.

Scope Title

Nutrient Recovery from Urine and Wastewater

Scope Description

Estimates for growing enough plants to support one human's food (dietary calories) suggest that 90-100 kg of fertilizer would be required per person per year. Even if plants were used only for partial life support (1/4 or 1/2 of the oxygen or food), this fertilizer mass would be substantial. NASA seeks methods and approaches for using in situ waste streams, such as urine and waste water to provide important nutrients and fertilizer for plants. Concepts should consider alternate approaches for how urine might be pre-treated to make it more amenable for fertilizer, and how the high levels of sodium typically found in urine might be separated or managed, since most plants are not tolerant to high levels of sodium.

References

Carter, D.L., et al. 2017. Status of ISS water management and recovery. ICES-2016-036.

Gitelson, J.I., I.A. Terskov, B.G. Kovrov, R. Ya. Sidko, G.M. Lisovsky, Yu. N. Okladnikov, V.N. Belyanin, I.N. Trubachov, and M.S. Rerberg. 1976. Life support system with autonomous control employing plant photosynthesis. Acta Astronautica, 3, 633-650.

Jackson, W.A., A. Morse, N. Landes and D. Low. 2010. An optimum biological reactor configuration for water recycling in space. ICES 2009-01-2564.

Lunn, G.M., G.W. Stutte, L.E. Spencer, M.E. Hummerick, L. Wong, R.M. Wheeler. 2017. Recovery on nutrients from inedible biomass of tomato and pepper to recycle fertilizer. Intl. Conf. on Environmental Systems ICES-2017-060.

Lynch, V.H., E.C.B. Ammann, and R.M. Godding. 1964. Urine as a nitrogen source for photosynthetic gas exchangers. Aerospace Med. 35:1067-1071.

Muirhead, D. 2011. Urine stabilization for enhanced water recovery in closed-loop life support systems.  ICES-2011. AIAA Technical Paper.

Macler, B.A. and R.D. MacElroy. 1989. Productivity and food value of Amaranthus cruentus under non-lethal salt stress. Adv. Space Res. 9(8):135-139.

Resh, H. 1989. Hydroponic food production: A definitive guide book of soilless food growing methods. Woodbridge Press Publ. Comp., Santa Barbara, CA, USA. 462 pages.

Subbarao, G.V., R.M. Wheeler, G.W. Stutte, and L.H. Levine. 1999. How far can sodium substitute for potassium in red beet? J. Plant Nutrition 22:1745-1761.

Wheeler, R.M., C.L. Mackowiak, W.L. Berry, G.W. Stutte, N.C. Yorio, and J.C. Sager. 1999. Nutrient, acid, and water budgets of hydroponically grown crops. Acta Hort. 481:655-661.

Wignarajah, K, S. Pisharody, M. Maron, and J. Fisher. 2001. Potential for recovery of plant macronutrients from space habitat wastes for salad crop production. SAE Technical Paper 2001-01-2350.

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Hardware, Research

Desired Deliverables Description

Phase I proposals should at a minimum deliver proof of concept for retrieving useful plant nutrients and removal / partitioning sodium from urine or ersatz urine wastewater. By the completion of Phase II, we hope to have prototypic or engineering development unit hardware delivered to NASA for the technology. The potential for Phase III funding for spaceflight validation would then be explored.

State of the Art and Critical Gaps

Current approaches for fertilizing plants for space depend largely on time-release fertilizer pellets that are mixed in with a solid rooting media (used both in Veggie and APH). This approach is not sustainable for multiple crop cycles and requires that all the fertilizer be delivered from Earth. Hydroponic approaches have been suggested for space (e.g., AES NextSTEP AstroGarden) and will hopefully be tested soon on the International Space Station (ISS), and eventually on surface settings. In this case, fertilizer salts would be mixed with water to provide a nutrient solution for the plants. Growing plants in space would be more sustainable if the cost and amount of fertilizer salts could be reduced by using recycled wastes, including processed urine.

Relevance / Science Traceability

This technology would be relevant and science traceable to:

• Human Exploration and Operations Mission Directorate (HEOMD): Space Life and Physical Science (SLPSRA)
• HEOMD: Advanced Exploration Systems (AES)
• HEOMD: Human Research Program (HRP)
• Space Technology Mission Directorate (STMD): Game Changing Development (GCD)
• STMD: Space Technology Research Institute (STRI)

Scope Title

Ethylene Gas Sensor

Scope Description

Ethylene is a 2-carbon alkene gas that has growth regulating effects on plants. Plants can produce ethylene through natural metabolic processes, and this ethylene can accumulate in closed environments (such as closed plant growth chambers) and have undesirable effects on the plants. These effects can include reduced growth, impaired pollen development and/or fertilization, leaf epinasty, flower abortion, accelerated fruit ripening, and more (Abeles et al., 1992). Being hormonal in nature, ethylene can affect plants at very low concentrations, with levels as low as 25 ppb being reported to have subtle effects on some plants. More sophisticated plant growth chambers for space have included ethylene removal systems, such as KMnO₄ coated pellets, but this is a consumable material and adds resistance to air circulation in the chamber. Real time ethylene monitoring would allow more judicious use of ethylene removal for controlling plant growth, and save on consumables. NASA seeks a miniature, sensitive (25 ppb), real time or near-real time sensor to monitor ethylene in plant growth environments for space. 

References

Abeles, F.B., P.W. Morgan, and M.E. Saltveit. 1992. Ethylene in plant biology. Vol. 3, Academic Press, Inc. San Diego, Calif.

Cushman, K.E. and T.W. Tibbitts. 1998. The role of ethylene in the development of constant-light injury of potato and tomato. J. Amer. Soc. Hort. Sci. 123:239-245.

He, C., R.T. Davies, and R.E. Lacey. 2009. Ethylene reduces gas exchange and growth of lettuce plants under hypobaric and normal atmospheric conditions. Physiol. Plant. 135:258-271.

Klassen, S.P. and B. Bugbee. 2002. Sensitivity of wheat and rice to low levels of atmospheric ethylene. Crop Science 42:746-753.

Monje, O., J.T. Richards, I. Eraso, T. P. Griffin, K.C. Anderson, and J.C. Sager. 2005. Designing a reusable ethylene filter cartridge for plant flight hardware: Characterization of thermally desorbing compounds. SAE Tech. Paper 2005-01-2953.

Wheeler, R.M., B.V. Peterson, and G.W. Stutte. 2004. Ethylene production throughout growth and development of plants. HortScience 39 (7):1541-1545.    

Expected TRL or TRL range at completion of the project: 4 to 7

Desired Deliverables of Phase II

Prototype, Hardware, Research

Desired Deliverables Description

Phase I proposals should at a minimum deliver proof of concept for a principle to detect ethylene real-time to a target level of 25 ppb. By the completion of Phase II, we hope to have prototypic or engineering development unit hardware delivered to NASA for the technology. The potential for Phase III funding for spaceflight validation with hardware like the Veggie or Advanced Plant Habitat chambers would then be explored.

State of the Art and Critical Gaps

Ethylene monitoring has traditionally been conducted using gas chromatography with either flame ionization or photo-ionization detection. However, gas chromatographs can be large instruments and require collection of gas samples, which are then analyzed. This limits their use in small spaces/volumes and their ability to analyze gases real-time. 

Relevance / Science Traceability

This technology would be relevant and science traceable to:

• Human Exploration and Operations Mission Directorate (HEOMD): Space Life and Physical Science (SLPSRA)
• HEOMD: Advanced Exploration Systems (AES)
• HEOMD: Human Research Program (HRP)
• Space Technology Mission Directorate (STMD): Game Changing Development (GCD)

STMD: Space Technology Research Institute (STRI)

Scope Title
Radioprotectors and Mitigators of Space Radiation-Induced Health Risks

Scope Description

Space radiation is a significant obstacle when sending humans on long-duration missions beyond low earth orbit. Although various forms for radiation exist in space, astronauts during Lunar or Mars missions will be exposed constantly to galactic cosmic radiation (GCR), which consists of high energy particles ranging from protons to extremely heavy ions. Astronaut health risks from space radiation exposure are categorized into cancer, late and early central nervous systems (CNS) effects, and degenerative risks, which include cardiovascular diseases and premature aging. With the current exposure limits for cancer risks, few female astronauts will be able to fly long duration missions without countermeasures.

This subtopic solicits proposals to develop biological countermeasures that mitigate one or several of the radiation risks associated with space travel. Compounds that target common pathways (e.g., inflammation) across aging, cancer, cardiovascular disease and neurodegeneration would be preferred. Most of the countermeasure developments in the medical arena have focused on mitigating the effects of X- or gamma rays. The proposed project should focus on re-purposing of technology and compounds for high-energy charged-particle applications. Compounds that are under current development or have been proven effective for other applications are both suitable for this subtopic.

In Phase I of the project, the company should test radioprotectors or mitigators using protons or other charged particles at doses simulating exposure to space radiation. This testing can be done with cell models at the location of choice. Deliverables for the Phase I will be data generated from this exposure with the radioprotector selected. After contract award, due to the nature of this research, the contractor should immediately coordinate with their technical monitor for any special considerations for testing. In Phase II of the project, we would expect the company to expand testing radioprotectors or mitigators with combinations of different particles and energies that simulate the space radiation environment. Appropriate animal models, which may include chimeric humanized mouse models, should be used for the Phase II project.

This subtopic seeks technology development that benefits the Space Radiation Element of the NASA Human Research Program (HRP). Biomedical countermeasures are needed for all of the space radiation risks.

References

The following references discuss the different health effects NASA has identified in regard to space radiation exposure:

• Evidence report on central nervous systems effects - https://humanresearchroadmap.nasa.gov/evidence/reports/CNS.pdf [162].
• Evidence report on degenerative tissue effects - https://humanresearchroadmap.nasa.gov/evidence/reports/Degen.pdf [163].
• Evidence report on carcinogenesis - https://humanresearchroadmap.nasa.gov/evidence/reports/Cancer.pdf [164].

Expected TRL or TRL range at completion of the project 5 to 8

Desired Deliverables Description

Phase I will test radioprotectors or mitigators using protons or other charged particles at space relevant doses. This testing can be done with cell models at the location of choice. After contract award, due to the nature of this research, the contractor should immediately coordinate with their technical monitor for any special considerations for testing.

Phase II will test effective radioprotectors or mitigators in space radiation simulated environments (HZE) to determine if they are able to minimize or prevent space radiation risks. Companies should provide a test plan for in vivo evaluation that describes the expected effect from the compound. Testing in NASA-owned space radiation simulation facilities will be an option for Phase II.

State of the Art and Critical Gaps

Exposure of crew members to space radiation during Lunar and Mars missions can potentially impact the success of the missions and cause long-term diseases. Space radiation risks include cancer, late and early CNS effects, cardiovascular diseases, and accelerated aging. Abiding by the current exposure limits for cancer risks, few female astronauts will be able to fly long-duration missions. Mitigation of space radiation risks can be achieved with physical (shielding) and biomedical means. This subtopic addresses development of drugs that mitigate one or several of the identified space radiation risks. Countermeasures for adverse health effects from radiation exposure are of interest to Department of Defense (DoD), Department of Homeland Security (DHS) and the radiation therapy community as well.

Relevance / Science Traceability

This subtopic seeks technology development that benefits the Space Radiation Element of the NASA Human Research Program (HRP). Biomedical countermeasures are needed for all of the space radiation risks.

Scope Title
Autonomous Medical Operations

Scope Description

Current medical operations on the International Space Station (ISS) rely significantly on the Mission Control Center (MCC) and telemedicine to enable Crew Health and Performance (CHP).  Near real-time communications allow MCC staff (Flight Surgeons, Flight Controllers, etc.) to guide the crew when a medical scenario exceeds the crew’s knowledge, skills or abilities. Prior to launch, crew are trained in the basic operation of the medical assets on the ISS and use detailed procedures to respond to a variety of planned and unplanned events. The training and procedures, however, are limited and do not adequately address the breadth of medical situations that may arise in flight. MCC expertise extends these capabilities allowing the crew to respond to an even larger set of events. Despite this, it is possible that some events will exceed the crew's and MCC’s ability to respond and will require the crew to rapidly return to earth and seek definitive medical care in a hospital.

Mars missions, however, will not have real-time communications with MCC nor will they have a rapid return capability. Round trip communications between the surface of Mars and Earth is approximately 40 minutes and the return trip will be months, which significantly complicates NASA’s current medical operations. Communication bandwidth considerations may also limit data transmission between the crew and MCC even in the event of high acuity medical situations. More specifically, a variety of existing ISS medical operations require the crew to ‘Contact MCC’ or ‘Notify Surgeon’ for additional instructions, a capability that will be significantly reduced on Mars. Examples of existing ISS medical operations can be found within the links found in the references section.

NASA requires new technologies that will enable a greater degree of autonomy and self-reliance for the crew and allow them to operate in a progressively Earth independent manner. These technologies should also be dual-purposed to enable MCC to better monitor and predict adverse conditions. Ideally, these solutions should require minimal mass, volume, power and/or crew time.  Examples of technology developments can include, but are not limited to, advanced just-in-time training modalities, enhanced procedure execution technologies (augmented reality), autonomous physiologic monitoring and trend prediction, automated and in-situ diagnostic and image interpretation, multipurpose medical supplies and devices, etc. The best technology solutions will 1) maximize crew autonomy and self-reliance across a wide range of medical operations, 2) demonstrate how technology could be leveraged to prevent adverse medical conditions, and 3) extend the amount of time needed before MCC intervention is required.

References

http://spaceref.com/iss/medical.ops.html [166]

https://www.nasa.gov/hrp/elements/exmc [167]

Expected TRL or TRL range at completion of the project 2 to 4

Desired Deliverables of Phase II

Prototype, Hardware, Software

Desired Deliverables Description

Phase I Deliverable - Conceptual prototype of a monitoring device/algorithm and final report detailing the conceptual prototype and hardware/software development plans.

Phase II Deliverable - Completed monitoring device/algorithm, and final report on the development, testing, and validation of the tool.

State of the Art and Critical Gaps

There are a variety of innovative technologies that are being developed, but the bulk of this technology is either not yet in clinical practice or has not been translated to a clinical domain.

Relevance / Science Traceability

A significant portion of ISS Medical Operations procedures require MCC to properly execute a medical procedure.  Contacting MCC on Mars will be significantly limited and technologies need to be developed that allow the crew to operate for longer periods of time without direct MCC interaction.

Scope Description

This subtopic seeks technologies related to cryogenic propellant (e.g. hydrogen, oxygen, methane) production, storage, transfer, and usage to support NASA's in-situ resource utilization (ISRU) goals. This includes a wide range of applications, scales, and environments consistent with future NASA missions to the Moon and Mars. Anticipated outcome of Phase I proposals are expected to deliver proof of the proposed concept with some sort of basic testing or physical demonstration. Proposals shall include plans for a prototype and demonstration in a defined relevant environment (with relevant fluids) at the conclusion of Phase II. Solicited topics are as follows:

• Subgrid Computational Fluid Dynamics (CFD) model that would model spray transport heat transfer and wall interactions during spray heat transfer during cryogenic propellant tank chilldown and fill in microgravity. Three submodels should be developed, including a (1) droplet transport and heat and mass transfer model, (2) fluid-to-wall boiling model covering all pertinent regimes (flash evaporation, film boiling, transition boiling, nucleate boiling, condensation), and (3) model that is used to capture bulk phases (e.g., volume of fluid). There should be seamless coupling between all three submodels. Emphasis should be on cryogenic fluids such as liquid hydrogen, oxygen, methane, and nitrogen. Phase I should have an emphasis on 1-g while Phase II should include microgravity applications. Models must be anchored to experimental cryogenic data.
• Develop and demonstrate methodologies for recovering propellant from lunar and Martian descent stages that have low fill levels (< 5%) of liquid oxygen, hydrogen, and/or methane mixed with helium. Methodologies can assume liquid extraction (for a short amount of time) or vapor extraction. Possible uses of the fluids could include fuel cells, life support/breathing air, or other applications. Methodologies should focus on the amount of propellant that might be extractable at different purities (prop/helium). Phase I should focus on defining and refining the methodologies for scavenging, as well as defining what should be done to the landers to enable or facilitate later access for scavenging. Phase II should include some sort of a demonstration, perhaps using simulant or similar fluids.
• Develop and defend a proposed relaxed propellant grade specification for liquid oxygen, liquid methane, and/or liquid hydrogen, allowing higher amounts of water contaminants in the oxygen and hydrogen, and higher amounts of water, hydrogen, and carbon monoxide/dioxide in the methane. Starting with assessment of potential impurities coming out of the ISRU production plant, analysis should evaluate the effects on the liquefaction system, pump and pressure-fed propellant feed system, and engine performance, especially potential stability effects. Phase I should conclude with a proposed relaxed propellant specification for at least one propellant (oxygen or methane priority over hydrogen), with identification of the propulsion component (liquefaction, feed system, injectors, etc.) that has the most sensitivity to the impurities and will therefore drive the limits on the specification. Phase II should include a hardware demonstration of the critical element at a minimum to validate the accuracy of the analytical predictions.
• Advance non-liquid electrolyte technologies for chemical flow cells (e.g., fuel cells, electrolyzers, flow batteries, etc.) that generate electrical power from a chemical reaction or reconstitute a reaction byproduct into fuels and oxidizer for such a chemical flow cell. These electrolytes are required to be cycled through very low temperatures (< 150 K) during storage to survive a lunar night or cis-lunar travel and recover completely (>98%) mechanical, electrical, and chemical performance. Ideally, these electrolytes would be able to process propellants (hydrogen, oxygen, methane, kerosene, etc.) and either tolerate or recover from exposure to standard propellant contaminants with minimal/no performance loss. Due to the potential for high fluid pressures and vibration loads, any proposal will illustrate how the electrolyte could be mechanically supported to operate hermetically under these conditions. To demonstrate that the electrolyte exceeds the State of Art, the deliverable test article will support an electrical current density of at least 300 mA/cm2 for at least 500 hours, support transient currents > 750 mA/cm2 for at least 30 seconds, and support slew rates > 50 A/cm2/s. Providing test data for the electrolyte performance degradation rate when operated as intended is required with test times >5,000 hours significantly strengthening the proposal. It would be beneficial if the electrolyte operated reversibly with equal efficiently. Liquid electrolytes, loose or contained within a support structure, are excluded from this Scope due to the complications that liquid electrolytes pose for an eventual system during launch.

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

References

1. Kartuzova, O., and Kassemi, M., "Modeling K-Site LH2 Tank Chilldown and no Vent Fill in Normal Gravity" AIAA-2017-4662

2. Chato, D. "LOX Tank Helium Removal for Propellant Scavenging Test" presentation at 2008 AIAA Aerospace Sciences Meeting, Orlando, FL, 2008.

3. Regenerative Fuel Cell Power Systems for Lunar and Martian Surface Exploration (https://arc.aiaa.org/doi/abs/10.2514/6.2017-5368 [169])

4. NASA Technology roadmap (https://gameon.nasa.gov/about/space-technology-roadmap/ [170]), §TA03.2.2.1.2. Chemical Power Generation and §TA03.2.2.2.3. Regenerative Fuel Cell Energy Storage (NOTE: This may be a dated link as this Roadmap still references ETDP/ETDD)

5. Commercial Lunar Propellant Architecture: A Collaborative Study of Lunar Propellant Production (https://doi.org/10.1016/j.reach.2019.100026 [171])

6. Linne, et.al. “Feasibility of Scavenging Propellants from Lander Descent Stage to Supply Fuel Cells and Life Support,” AIAA-2009-6511, September, 2009.    

Expected TRL or TRL range at completion of the project: 2 to 4

Desired Deliverables of Phase II

Prototype, Hardware, Software

Desired Deliverables Description

Phase I proposals should at minimum deliver proof of the concept, including some sort of testing or physical demonstration, not just a paper study. Phase II proposals should provide component validation in a laboratory environment preferably with hardware (or model subroutines) deliverable to NASA.

Electrolyte technologies for chemical cell product deliverables would be an operational electrochemical test article demonstrating the capability of the electrolyte to support the listed current density by processing the intended propellants when packaged as a flow cell. This test article will have an active area of at least 50 cm2 and would ideally contain multiple cells to demonstrate extensibility to existing stack designs. It would be favorable to include empirical electrochemical performance data of the electrolyte over as much of the pressure range from 5 psia to 3015 psia as possible to illustrate the potential viability range for Lunar applications.

State of the Art and Critical Gaps

Cryogenic Fluid Management is a cross-cutting technology suite that supports multiple forms of propulsion systems (nuclear and chemical), including storage, transfer, and gauging, as well as liquefaction of ISRU produced propellants.  Space Technology Mission Directorate (STMD) has identified that Cryogenic Fluid Management (CFM) technologies are vital to NASA's exploration plans for multiple architectures, whether it is hydrogen/oxygen or methane/oxygen systems including chemical propulsion and nuclear thermal propulsion. For spray transport and film condensation, there are significant gaps in modeling. For scavenging, only small scale tests have been conducted to remove residual helium from a liquid oxygen tank.

There is currently no standard on propellant grade specification for an ISRU plant.

Existing electrolytes for space applications are limited to a polymeric membrane based on perfluorinated teflon and ceramic electrolyte. While it has the necessary electrochemical and mechanical properties, the polymeric membrane has very tight thermal constraints due to a high moisture content which complicates thermal system designs for lunar systems during transit. It is also very sensitive to chemical contamination. The ceramic electrolyte has significant mechanical and slew rate limitations, but is more resilient to chemical contamination and has a much larger thermal range which allows storage in very cold environments. Once operational and at temperature, either existing electrolyte technology operates in cold lunar regions. Should an off-nominal event occur during the lunar night that results in a cold-soak, neither existing electrolyte technology has a meaningful chance of recovering from the exposure to the low temperatures.

Relevance / Science Traceability

STMD strives to provide the technologies that are needed to enable exploration of the solar system, both manned and unmanned systems; cryogenic fluid management is a key technology to enable exploration. Whether liquid oxygen/liquid hydrogen or liquid oxygen/liquid methane is chosen by Human Exploration and Operations Mission Directorate (HEOMD) as the main in-space propulsion element to transport humans, CFM will be required to store propellant for up to 5 years in various orbital environments. Transfer will also be required, whether to engines or other tanks (e.g., depot/aggregation), to enable the use of cryogenic propellants that have been stored. In conjunction with ISRU, cryogens will have to be produced, liquefied, and stored, the latter two of which are CFM functions for the surface of the Moon or Mars. ISRU and CFM liquefaction drastically reduces the amount of mass that has to be landed on the Moon or Mars.

NASA already has proton exchange-membrane (PEM) based electrochemical hardware in the International Space Station (ISS) Oxygen Generator Assembly and is developing electrochemical systems for space applications through the Evolved Regenerative Fuel Cell. These system designs could be readily adapted to a solid electrolyte with capabilities beyond the existing State of Art for specific applications such as In Situ Resource Utilization, lunar fuel cell power systems, or regenerative fuel cell energy storage systems. As Commercial Lunar Payload Services (CLPS) companies have identified primary fuel cell power systems as a required technology, it would be helpful to ensure that there are options available that could survive the lunar night when off-line without active thermal control. This would enable a longer period between missions to re-fuel and recover the electrochemical system.

Scope Title
Solar Concentrator Technologies for Oxygen Extraction and In-Situ Construction

Scope Description

Solar concentrators have been used to successfully demonstrate multiple In-Situ Resource Utilization (ISRU) technologies including hydrogen and carbothermal reduction, sintering of surfaces pads, and production of blocks for construction. Terrestrial state of the art solar concentrators are heavy, not designed for easy packaging/shipping and assembly/installation, and can be maintained and cleaned on a periodic basis to maintain performance. For ISRU space applications, NASA is interested in solar concentrators that are able to be packaged into small volumes, are light weight, easily deployed and set up, can autonomously track the sun, and can perform self-cleaning operations to remove accumulated dust. Materials, components, and systems that would be necessary for the proposed technology must be able to operate on the lunar surface: up to 110^oC (230^oF) during sunlit periods and survive temperatures down to -170oC (-274^oF) during periods of darkness. Systems must also be able to operate for at least one year with a goal of 5 years without substantial maintenance in the dusty regolith environment. Proposers should assume that regolith mining operations will be tens of meters away from the solar concentrators, but that regolith processing systems and solar concentrators will be co-located on a single lander. Phase 1 efforts can be demonstrated at any scale, Phase 2 efforts must be scalable up to 11.1 kW of delivered solar energy assuming an incoming solar flux of ~1350 W/m2 while also considering volumetric constraints for launch and landing. Each of the following specific areas of technology interest may be developed as a standalone technology, but proposals that address multiple areas are encouraged.

Lightweight Mirrors/Lenses: Proposals must clearly state the estimated W/kg for the proposed technology. Phase 2 deliverables must be deployed and supported in Earth 1-g (without wind loads) but should include design recommendations for mass reductions for lunar gravity (1/6-g) deployment. Proposals should address the following attributes: high reflectivity, low coefficient of thermal expansion, strength, mass, reliability and cost.

(See Z13.01 - Active and Passive Dust Mitigation Surfacesto propose dust repellent mirror/lens related technologies. This will help to solve issues where dust particles cling to the surface of a mirror or lens and degrade the performance of a solar concentrator.)

Efficient transmission of energy for oxygen/metal extraction: While the solar concentrator will need to move to track the sun, reactors requiring direct thermal energy for oxygen extraction will be in a fixed position and orientation. Concentrated sunlight must be able to be directed to a single or multiple spots to effectively heat or melt the regolith. Proposals must define the expected transition losses from collection to delivery and should capture any assumptions made regarding the distance from collection to delivery.

Sintering end effector: Solar concentrators have been used to demonstrate the fabrication of 3D printed components using regolith as the only feedstock. However, an end effector designed to melt regolith at 1600^oC will not be optimized for selective sintering. Proposals responding to this specific technology area must produce a focal point temperature between 1000^oC to 1100^oC for the purpose of sintering lunar regolith.

References

Gordon, P. E., Colozza, A. J., Hepp, A. F., Heller, R. S., Gustafson, R., Stern, T., & Nakamura, T. (2011). Thermal energy for lunar in situ resource utilization: technical challenges and technology opportunities.

Nakamura, T., & Smith, B. (2011, January). Solar thermal system for lunar ISRU applications: development and field operation at Mauna Kea, HI. In 49th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition (p. 433).

Gustafson, R., White, B., Fidler, M., & Muscatello, A. (2010). Demonstrating the solar carbothermal reduction of lunar regolith to produce oxygen. In 48th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition (p. 1163).

Expected TRL or TRL range at completion of the project: 3 to 4

Desired Deliverables of Phase II

Prototype

Desired Deliverables Description

TRL4 hardware that can be deployed during a field demonstration

State of the Art and Critical Gaps

The 2011 paper Thermal Energy for Lunar in Situ Resource Utilization: Technical Challenges and Technology Opportunities summarized the work performed in this area and recommends future efforts focus on lightweight mirrors (possibly using composite materials) and dust mitigation techniques.

The last solar concentrator system developed for ISRU had an overall efficiency of ~33%. The performance of the system is captured in the 2011 Paper Solar thermal system for lunar ISRU applications: development and field operation at Mauna Kea, HI

Relevance / Science Traceability

The last time NASA was focused on a lunar destination, solar concentrators were used for multiple ISRU applications.

Scope Title
Novel Oxygen Extraction Concepts

Scope Description

Lunar regolith is approximately 45% oxygen by mass. The majority of the oxygen is bound in silicate minerals.  Previous efforts have shown that it is possible to extract oxygen from silicates using various techniques such as carbothermal reduction and molten regolith electrolysis. NASA is interested in developing novel oxygen extraction systems that can be proven to handle large amounts of lunar regolith throughput, while minimizing consumables, mass and energy.

• Phase 1 demonstrations can be at any scale, but eventually the technology must be able to demonstrate an average rate of 1.85 kg O₂/hr (10 metric tons of Oxygen in 225 days).
• Phase 2 demonstrations can be subscale, but must define the number of subscale units necessary to achieve an average extraction rate of 1.85 kg O₂/hr.
• Demonstrations do not need to produce actual oxygen gas, but can end at a reaction product that has successfully removed oxygen atoms from the silicate mineral.
• Proposers need to define any Earth supplied reagents or hardware that might be consumed or need to be recycled and should estimate replenishment or loss rates expected.
• Proposals should state expected energy requirements (both electrical and thermal) as well as temperatures at which the proposed process will operate.
• Proposers should estimate Wh/kg 0₂ for concepts and/or provide a plan to determine that value as part of the effort.
• Proposers should address how concepts can be shutdown and restarted.
• Proposers should address the ability of a concept to be able to operate for at least one year with a goal of 5 years without substantial maintenance.

References

1. Gustafson, R., White, B., & Fidler, M. (2011, January). 2010 field demonstration of the solar carbothermal regolith reduction process to produce oxygen. In 49th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition (p. 434).
2. Sirk, A. H., Sadoway, D. R., & Sibille, L. (2010). Direct electrolysis of molten lunar regolith for the production of oxygen and metals on the moon. ECS Transactions, 28(6), 367-373.

Expected TRL or TRL range at completion of the project: 4 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Research

Desired Deliverables Description

TRL 4-6 hardware that can demonstrate a scalable oxygen extraction process in a manner that accommodates the movement of material through the extraction zone.

State of the Art and Critical Gaps

The carbothermal reduction process was demonstrated at a relevant scale using an automated reactor in 2010. The approach was successful but used many moving parts and was never life tested for the types of durations that will be required on the lunar surface. Molten Regolith Electrolysis has been demonstrated at the bench scale, but current designs lack a means to move regolith in and out of the oxygen extraction zone. Both processes are used terrestrially, but industrial designs do not provide a means to keep gases from escaping to the vacuum of space.

Relevance / Science Traceability

STMD (Space Technology Mission Directorate) has identified the need for oxygen extraction from regolith. The alternative path, oxygen from lunar water, currently has much more visibility. However, we currently do not know enough about the concentration and accessibility of lunar water to know if it would offer a better return on energy investment than oxygen extracted from the regolith. A lunar water prospecting mission is required to properly assess the utilization potential of water on the lunar surface. Until water prospecting data becomes available, NASA recognizes the need to make progress on the technology needed to extract oxygen from dry lunar regolith. 

Scope Title
Lunar Ice Mining

Scope Description

We now know that water ice exists on the poles of the Moon from data obtained from missions like the Lunar Prospector, Chandrayaan-1, Lunar Reconnaissance Orbiter (LRO) and the Lunar Crater Observation and Sensing Satellite (LCROSS). We know that water is present in Permanently Shadowed Regions (PSR), where temperatures are low enough to keep water in a solid form despite the lack of atmospheric pressure. One challenge with extracting the water is that desorption and sublimation can occur at temperatures as low as 150 Kelvin. The inverse challenge exists with water collection. Unless the water vapor is under pressure, extremely cold temperatures will be necessary to capture it. NASA is seeking methods to acquire lunar water ice from permanently shadowed regions. Proposals must describe a method for extracting and/or collecting lunar water ice that exists at temperatures between 40 to 100 Kelvin and 10-9 torr vacuum.

• Phase 1 demonstrations can be at any scale, but eventually the technology must be able to demonstrate an average rate of 2.78 kg H₂O/hr (15 metric tons of water in 225 days).
• Phase 2 demonstrations can be subscale, but must define the number of subscale units necessary to achieve an average extraction rate of 2.78 kg H₂O/hr.
• Proposals should state expected energy requirements (both electrical and thermal).
• Proposers should assume a mobile platform is considered to be available, but should not be necessary for technology demonstration.
• Proposers should state their assumptions about water ice concentration.
• Proposals should describe a tolerance for a trace amount of organics or volatiles that may accumulate on collection surfaces.
• Proposers should estimate Wh/kg H₂0 for concepts and/or provide a plan to determine that value as part of the effort.
• Proposers should address the ability of a concept to be able to operate for at least one year with a goal of 5 years without substantial maintenance.

Estimates for mass and volume of the final expected hardware should be specified.

References

Colaprete, A., Schultz, P., Heldmann, J., Wooden, D., Shirley, M., Ennico, K., & Goldstein, D. (2010). Detection of water in the LCROSS ejecta plume. Science, 330(6003), 463-468.

Hibbitts, C. A., Grieves, G. A., Poston, M. J., Dyar, M. D., Alexandrov, A. B., Johnson, M. A., & Orlando, T. M. (2011). Thermal stability of water and hydroxyl on the surface of the Moon from temperature-programmed desorption measurements of lunar analog materials. Icarus, 213(1), 64-72.

Poston, M. J., Grieves, G. A., Aleksandrov, A. B., Hibbitts, C. A., Darby Dyar, M., & Orlando, T. M. (2013). Water interactions with micronized lunar surrogates JSC‐1A and albite under ultra‐high vacuum with application to lunar observations. Journal of Geophysical Research: Planets, 118(1), 105-115.

Andreas, E. L. (2007). New estimates for the sublimation rate for ice on the Moon. Icarus, 186(1), 24-30.

Expected TRL or TRL range at completion of the project 4 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware

Desired Deliverables Description

TRL 4-5 hardware that can demonstrate scalable water ice extraction technology in a relevant environment

State of the Art and Critical Gaps

Scoops and bucket-wheel excavators have been demonstrated for the collection of unconsolidated material but may not be effective at excavating consolidated regolith-ice composites. The Planetary Volatiles Extractor (PVEx) developed by Honeybee Robotics is the state of the art for heated core drills, but life testing is required to determine the rate of wear due to repeated excavation. Multiple groups have investigated the use of thermal mining methods to separate water from regolith, but the depth of water removed is relatively shallow. Very little work has been performed on the ability to capture water in a lunar environment after it has been released from the surface.

Relevance / Science Traceability

The current NASA Administrator has referenced water ice as one of the reasons we have chosen the lunar poles as the location to establish a sustained human presence. STMD has identified the need for water extraction from permanently shadowed regions. Multiple mission directorates over the past several years have provided funding for a water prospecting mission so that we can gain the information required to establish an ice mining architecture.

Scope Description

NASA recognizes the potential of lidar technology to meet many of its science objectives by providing new capabilities or offering enhancements over current measurements of atmospheric and topographic parameters from ground, airborne, and space-based platforms. To meet NASA’s requirements for remote sensing from space, advances are needed in state-of-the-art lidar technology with an emphasis on compactness, efficiency, reliability, lifetime, and high performance. Innovative lidar subsystem and component technologies that directly address the measurement of atmospheric constituents and surface topography of the Earth, Mars, the Moon, and other planetary bodies will be considered under this subtopic. Compact, high-efficiency lidar instruments for deployment on unconventional platforms, such as balloons, SmallSats, and CubeSats are also considered and encouraged.

Proposals must show relevance to the development of lidar instruments that can be used for NASA science-focused measurements or to support current technology programs. Meeting science needs leads to four primary instrument types:

• Backscatter - Measures beam reflection from aerosols to retrieve the opacity of a gas.
• Ranging - Measures the return beam’s time-of-flight to retrieve distance.
• Doppler - Measures wavelength changes in the return beam to retrieve relative velocity.
• Differential absorption - Measures attenuation of two different return beams (one centered on a spectral line of interest) to retrieve concentration of a trace gas. 

References

NASA missions are aligned with the National Research Council's decadal surveys, with the latest survey published in 2018 under the title "Thriving on Our Changing Planet: A Decadal Strategy for Earth Observation from Space" (http://sites.nationalacademies.org/DEPS/esas2017/index.htm [175]).

NASA lidar applications and technology needs for Earth Science are also summarized in the report
"NASA ESTO Lidar Technologies Investment Strategy: 2016 Decadal Update." (https://ntrs.nasa.gov/search.jsp?R=20180002566 [176])

Conference proceedings on NASA lidar interests in earth science, exploration, and aeronautics can be found at the Technical Interchange Meeting on Active Optical Systems (https://www.nasa.gov/nesc/tim-active-optical-systems [177])

Expected TRL or TRL range at completion of the project 3 to 6

Desired Deliverables of Phase II

Prototype, Hardware, Software

Desired Deliverables Description

Phase I research should demonstrate technical feasibility and show a path toward a Phase II prototype unit. Phase II prototypes should be capable of laboratory demonstration and preferably suitable for operation in the field from a ground-based station, an aircraft platform, or any science platform amply defended by the proposer.

State of the Art and Critical Gaps

• Compact and rugged single-frequency continuous-wave and pulsed lasers operating between 290-nm and 2050-nm wavelengths suitable for lidar. Specific wavelengths are of interest to match absorption lines or atmospheric transmission: 290 to 320-nm (ozone absorption), 450 to 490-nm (ocean sensing), 532-nm, 817-nm (water line), 935-nm (water line), 1064-nm, 1570-nm (CO2 line), 1650-nm (methane line), and 2050-nm (Doppler wind). Architectures involving new developments in diode laser, quantum cascade laser, and fiber laser technology are especially encouraged. For pulsed lasers two different regimes of repetition rate and pulse energies are desired: from 1-kHz to 10-kHz with pulse energy greater than 1-mJ and from 20-Hz to 100-Hz with pulse energy greater than 100-mJ. Laser sources of wavelength at or around 780-nm are not sought this year.
• Novel approaches and components for lidar receivers such as: integrated optical/photonic circuitry, compact and lightweight Cassegrain telescopes compatible with existing differential absorption lidar (DIAL) and HSRL lidar systems, frequency agile solar blocking filters at 817-nm and/or 935-nm, and scanners for large apertures of telescope of at least 10-cm diameter and scalable to 50-cm diameter.
• New space lidar technologies that use small and high-efficiency diode or fiber lasers to measure range and surface reflectance of planets or asteroids from >100-km altitude during mapping to < 1-m during landing or sample collection, within size, weight, and power fit into a 4U CubeSat or smaller. New lidar technologies that allow system reconfiguration in orbit, single photon sensitivities and single beam for long distance measurement, and variable dynamic range and multiple beams for near-range measurements.
• Transformative technologies and architectures are sought to vastly reduce the cost, size, and complexity of lidar instruments. Advances are needed in generation of high pulse energy (>> 1-mJ) from compact (CubeSat size) packages, avoiding the long cavity lengths associated with current solid-state laser transmitter designs. Mass-producible laser designs, perhaps by a hybrid diode/fiber/crystal architecture, are desirable for affordable sensor solutions and reducing parts count. Heat removal from lasers is a persistent problem, requiring new technologies for thermal management of laser transmitters. New materials concepts could be of interest for the reduction of weight for optical benches and telescopes. Distributed transmitter/receiver apertures may offer another option for weight reduction.

Relevance / Science Traceability

The proposed subtopic address many missions, programs, and projects identified by the Science Mission Directorate including:

Aerosols--ongoing and planned missions include ACE (Aerosols/Clouds/Ecosystems), PACE (Plankton, Aerosol, Cloud, ocean Ecosystems), and MESCAL (Monitoring the Evolving State of Clouds and Aerosols).

Greenhouse Gases--planned missions include sensing of carbon dioxide and methane. The ASCENDS (Active Sensing of CO2 Emissions over Nights, Days, and Seasons) mission was recommended by the Decadal Survey.

Ice Elevation--ongoing and planned missions include ICESat (Ice, Cloud, and land Elevation Satellite), as well as aircraft-based projects such as IceBridge.

Atmospheric Winds--planned missions include 3D-Winds, as recommended by the Decadal Survey. Lidar wind measurements in the Mars atmosphere are also under study in the MARLI (Mars Lidar for Global Climate Measurements from Orbit) program.

Planetary Topography--altimetry similar to Earth applications is being planned for planetary bodies such as Titan and Europa.

Gases related to Air Quality--planned missions include sensing of tropospheric ozone, nitrogen dioxide, or formaldehyde to support NASA projects such as TOLNet (Tropospheric Ozone Lidar Network) and the Pandora Global Network.

Automated Landing, Hazard Avoidance, and Docking--technology development is called for under programs and missions such as ALHAT (Autonomous Landing and Hazard Avoidance Technology), SPLICE (Safe and Precise Landing Integrated Capabilities Evolution), and NPLP (NASA Provided Lunar Payloads).

This subtopic supports technologies to aid NASA in its active microwave sensing missions. Specifically, we are seeking:

1 Watt G-band (167-175 GHz) Solid State Power Amplifier for Remote Sensing Radars - Future cloud, water, and precipitation missions require higher frequency electronics, with small form factors and high Power Added Efficiencies (PAE) in order to measure smaller particles and enable compact instruments. Solid state amplifiers that meet high efficiency (> 20% PAE) requirements and have small form factors would be suitable for SmallSats, support single satellite missions (such as RainCube), and enable future swarm techniques. No such devices at these high frequencies, high powers, and efficiencies are currently available. We expect a power amplifier with TRL 2-4 at the completion of the project.

GPS (Global Positioning System) Denied Timing Synchronization - This would enable multi-platform instruments to share timing, which is enabling for GPS-denied environments (e.g., planetary exploration or GPS-hostile locations on Earth such as the subsurface). Multi-static radar has many applications for planetary science, but is impractical due to the lack of universal timing systems, such as what GPS provides on Earth. A low SWaP (size, weight, and power) system would be enabling for small, multi-static radars to perform in non-terrestrial environments. We desire to wirelessly distribute a synchronized PPS and/or 10 MHz clock in a GPS-denied environment between multiple radar units with <0.5 ns accuracy. The system should perform at distances of up to 5 km; synchronization hardware should be low mass (<1 kg), low power (<1 W), and small size (<5x5x10 cm). Ideally, the system should have a path to flight qualification to be used for lunar and planetary science. Deliverables include design and analysis of potential solutions, for which realizable hardware exists or is plausibly able to be developed with current technology. We expect a system with TRL 2-4 at the completion of the project.

V Band SSPA (65-71 GHz) – We seek highly efficient solid-state power amplifier (SSPA) for pressure sensing. No commercial solutions exist that satisfy high power added efficiency and bandwidth in a form factor suitable for CubeSat/SmallSat platforms. The desired capability is for smallsats doing surface pressure sensing absorption radar using V-band. The total SSPA bandwidth desired is 65-71 GHz with a maximum power of 10+ Watts at 65 GHz and 1+ Watt at 70 GHz. The package should be suitable for CubeSat/SmallSat platforms with high power added efficiency. SSPA should be pulsed with a minimum duty cycle of 25% and be suitable for a spaceflight environment. Desired deliverables are V-band SSPA prototype. We expect TRL 4-5 at the completion of the project.

Extreme environments Digital-to-Analog Converter (DAC) – We seek a single chip (or single package) DAC, capable of surviving and maintaining performance in high radiation environments (~100's krad), including ELDRS (enhanced low dose rate sensitivity) in the range of approximately 0.5-10 mrad (Si)/s. This capability is relevant to planetary remote sensing. The DAC should support a sampling rate of 500Ms/s or higher, with an effective number of bits >6. The desired deliverable is a DAC prototype.

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

References

Radar in a CubeSat (RainCube): https://www.jpl.nasa.gov/cubesat/missions/raincube.php [179]

Global Atmospheric Composition Mission: https://www.nap.edu/read/11952/chapter/9 [180]

Global Precipitation Measurement Mission: https://www.nasa.gov/mission_pages/GPM/overview/index.html [181]

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Research

Scope Title

Components for addressing gain instability in Low Noise Amplifier (LNA) based radiometers from 100 and 600 GHz

Scope Description

NASA requires low insertion loss solutions to the challenges of developing stable radiometers and spectrometers operating above 100 GHz that employ LNA based receiver front ends. This includes noise diodes with Excess Noise Ratio (ENR) > 10dBm with better than ≤ 0.01 dB/°C thermal stability, Dicke switches with better than 30 dB isolation, phase modulators, and low loss isolators along with fully integrated state-of-art receiver systems operating at room and cryogenic temperatures.

Expected TRL or TRL range at completion of the project: 4 to 5

Desired Deliverables of Phase II

Prototype, Hardware

Desired Deliverables Description

Hardware to enable low-loss radiometer gain calibration above 100 GHz.

State of the Art and Critical Gaps

Traditional internal microwave radiometer gain instability calibration electronics become prohibitively lossy as the frequency increases above 100 GHz. As such, radiometers at this frequency are most commonly calibrated with external references. These are larger and more massive than internal calibration electronics.

Relevance / Science Traceability

Critical need: Immediate for future earth observing, planetary, and astrophysics missions. The wide range of frequencies in this scope are used for numerous science measurements such as earth science temperature profiling, ice cloud remote sensing, and planetary molecular species detection. 

Scope Title
Ultra Compact Radiometer

Scope Description

An ultra-compact radiometer of either a switching or pseudo-correlation architecture with internal calibration sources is needed. Designs with operating frequencies at the conventional passive microwave bands of 36.6 GHz (priority), 18.65 GHz, and 23.8 GHz enabling dual-polarization inputs. Interfaces include waveguide input, control, and digital data output. Ideal design features enable subsystems of multiple (10's of) integrated units to be efficiently realized.

Expected TRL or TRL range at completion of the project: 4 to 5

Desired Deliverables of Phase II

Prototype, Hardware

Desired Deliverables Description

Ultra-compact radiometer prototype.

State of the Art and Critical Gaps

Current microwave radiometers at this frequency are bulky with significant waveguide and coaxial interconnects. Dramatically smaller systems are desired for small SmallSat and CubeSat payloads, or for arrays of radiometer receivers.

Relevance / Science Traceability

This technology, in conjunction with deployable antenna technology, would enable traditional Earth land and ocean radiometry with significantly reduced instrument size, making it suitable for CubeSat or SmallSat platforms.

Scope Title
Correlating radiometer front-ends and low 1/f-noise detectors for 100-700 GHz

Scope Description

Low DC power correlating radiometer front-ends and low 1/f-noise detectors are required for 100-700 GHz. Deliverables should provide improved calibration stability, sensitivity, or 1/f noise performance compared to conventional total-power or Dicke / noise-injection radiometers at these frequencies.

Expected TRL or TRL range at completion of the project: 4 to 5

Desired Deliverables of Phase II

Prototype, Hardware

Desired Deliverables Description

Low DC power correlating radiometer front-ends and low 1/f-noise detectors for 100-700 GHz.

State of the Art and Critical Gaps

The low DC power consumption is critical for small missions, such as CubeSats. Low 1/f-noise of the detectors and correlating radiometers needed for radiometer stability across the scan for measurements at above 100 GHz for atmospheric humidity and cloud measurements as well as atmospheric chemistry.

Relevance / Science Traceability

The wide range of frequencies in this scope are used for numerous science measurements such as earth science temperature profiling, ice cloud remote sensing, and planetary molecular species detection.

Scope Title
Photonic Integrated Circuits for Microwave Remote Sensing

Scope Description

Photonic Integrated Circuits are an emerging technology for passive microwave remote sensing. NASA is looking for photonic integrated circuits for processing microwave signals in spectrometers, beam forming arrays, correlation arrays and other active or passive microwave instruments.

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Research

Desired Deliverables Description

PIC designs to enable increased capability in passive microwave remote sensing instruments. This is a low-TRL emerging technology, so vendors are encouraged to identify and propose designs where PIC technology would be most beneficial.

State of the Art and Critical Gaps

Photonic Integrated Circuits (PIC) are an emerging technology not used in current NASA microwave missions, but may enable significant increases in bandwidth.

Relevance / Science Traceability

PICs may enable significantly increased bandwidth of Earth viewing, astrophysics, and planetary science missions. In particular, this may allow for increased bandwidth or resolution receivers, with applications such as hyperspectral radiometry.

Scope Title
Spectrometer back ends for microwave radiometers

Scope Description

Technology for low-power, rad-tolerant broad band spectrometer back ends for microwave radiometers.

Possible Implementations Include:

• Digitizers starting at 20 Gsps, 20 GHz bandwidth, 4 or more bit and simple interface to FPGA;
• ASIC implementations of polyphase spectrometer digital signal processing with ~1 Watt/GHz.
• 5-GHz bandwidth polarimetric-spectrometer with 512 channels. Two simultaneously sampled ADC inputs. Spectrometer filter banks and either polarization combiners or cross correlators for computing all four Stokes parameters (any Stokes vector basis is acceptable: e.g., IQUV, vhUV, vhpmlr). Kurtosis detectors on at least the two principal channels. Rad-hard and minimized power dissipation.
• Combined radar/radiometer receiver with radiometer spectral processing (polyphase filter bank or FFT) synchronized with radar matched filtering and moment processing.

Expected TRL or TRL range at completion of the project: 4 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware

Desired Deliverables Description

The desired deliverable of this Subtopic Scope is a low-power Spectrometer ASIC or other component that can be incorporated into multiple NASA radiometers.

State of the Art and Critical Gaps

Current FPGA based spectrometers require ~10 W/GHz and are not flight qualifiable. High speed digitizers exist but have poorly designed output interfaces. Specifically designed ASICs could reduce this power by a factor of 10.

Relevance / Science Traceability

Broadband spectrometers are required for Earth observing, planetary, and astrophysics missions. Improved digital spectrometer capability is directly applicable to planetary science, and enables Radio Frequency Interference (RFI) mitigation for Earth science.

Scope Description

NASA is seeking new technologies or improvements to existing technologies to meet the detector needs of future missions, as described in the most recent decadal surveys:

• Earth Science and Applications from Space: http://www.nap.edu/catalog/11820.html [184]
• New Frontiers in the Solar System: http://www.nap.edu/catalog/10432.html [185]
• Astronomy and Astrophysics in the New Millennium: http://www.nap.edu/books/0309070317/html/ [186]

Technologies for visible detectors are not being solicited this year.

LOW-POWER & LOW-COST READOUT INTEGRATED ELECTRONICS

Photodiode Arrays: In-pixel Digital Readout Integrated Circuit (DROIC) for high dynamic range infrared imaging and spectral imaging (10-60 Hz operation) focal plane arrays to circumvent the limitations in charge well capacity, by using in-pixel digital counters that can provide orders of magnitude larger effective well depth, thereby affording longer integration times.

MKID/TES Detectors: A radiation tolerant, digital readout system is needed for the readout of low temperature detectors such as Microwave Kinetic Inductance Detector (MKIDs) or other detector types that use microwave frequency domain multiplexing techniques. Each readout channel of the system should be capable of generating a set of at least 1500 carrier tones in a bandwidth of at least 1 GHz with 14 bit precision and 1 kHz frequency placement resolution. The returning frequency multiplexed signals from the detector array will be digitized with at least 12 bit resolution. A channelizer will then perform a down-conversion at each carrier frequency with a configurable decimation factor and maximum individual subchannel bandwidth of at least 50 Hz. The power consumption of a system consisting of multiple readout channels should be at most 20 mW per subchannel or 30 W per 1 GHz readout channel. That requirement would most likely indicate the use of an RF System on a Chip or ASIC with combined digitizer and channelizer functionality.

Bolometric Arrays: Low power, low noise, cryogenic multiplexed readout for large format two-dimensional bolometer arrays with 1000 or more pixels, operating at 65-350 mK. We require a superconducting readout capable of reading two Transition Edge Sensors (TESs) per pixel within a 1 mm-square spacing. The wafer-scale readout of interest will be capable of being indium-bump bonded directly to two-dimensional arrays of membrane bolometers. We require row and column readout with very low crosstalk, low read noise \, and low detector Noise Equivalent Power degradation.

Thermopile Detector Arrays: Mars Climate Sounder (MCS), the Diviner Lunar Radiometer Experiment (DLRE), and the Polar Radiant Energy in the Far Infrared Experiment (PREFIRE) are NASA space-borne radiometers that utilize custom thermopile detector arrays. Next-generation radiometers will use larger format thermopile detector arrays, indium bump bonding to hybridize the detector arrays to the Readout Integrated Circuits (ROICs), low input-referred noise, and low power consumption. ROICs compatible with 128x64 element Bi-Sb-Te thermopile arrays with low 1/f noise, an operating temperature between 200-300 K, radiation hardness to 300 krad and on-ROIC analog-to-digital converter (ADC) will be desirable.    

LIDAR DETECTORS

Development of single-mode fiber-coupled extended-wavelength integrated InGaAs detectors/preamplifiers for heterodyne detection lidar at 2-2.1 um wavelengths with near shot-noise-limited performance for less than 3 mW local oscillator power, quantum efficiency > 90% over 2-2.1 um wavelengths, and bandwidth > 5 GHz. Specifications should be demonstrated in heterodyne detection experiments.

IR & Far-IR/SUBMILLIMETER-WAVE DETECTORS

Novel Materials and Devices: New or improved technologies leading to measurement of trace atmospheric species (e.g., CO, CH4, N2O) or broadband energy balance in the IR and far-IR from geostationary and low-Earth orbital platforms. Of particular interest are new direct detector or heterodyne detector technologies made using high temperature superconducting films (YBCO, MgB2) or engineered semiconductor materials, especially 2-Dimensional Electron Gas (2DEG) and Quantum Wells (QW).

Array Receivers: Development of a robust wafer level packaging/integration technology that will allow high-frequency capable interconnects and allow two dissimilar substrates (i.e., Silicon and GaAs) to be aligned and mechanically 'welded' together. Specially develop ball grid and/or Through Silicon Via (TSV) technology that can support submillimeter-wave (frequency above 300 GHz) arrays.

Receiver Components: Local Oscillators capable of spectral coverage 2-5 THz; Output power up to > 2 mW; Frequency agility with > 1 GHz near chosen THz frequency; Continuous phase-locking ability over the THz  tunable range with < 100 kHz line width. Both solid-state (low parasitic Schottky diodes) as well as Quantum Cascade Lasers (for f > 2 THz) will be needed. Components and devices such as mixers, isolators, and orthomode transducers, working in the THz range, that enable future heterodyne array receivers are also desired. GaN based power amplifiers at frequencies above 100 GHz and with PAE > 25% are also needed. ASIC based SoC (System on Chip) solutions are needed for heterodyne receiver backends. ASICs capable of binning > 6 GHz intermediate frequency bandwidth into 0.1-0.5 MHz channels with low power dissipation < 0.5 W would be needed for array receivers

References

1. Meixner, M. et al., “Overview of the Origins Space telescope: science drivers to observatory requirements,” Proc. SPIE 10698 (2018).
2. Leisawitz, D. et al., “The Origins Space telescope: mission concept overview,” Proc. SPIE 10698 (2018).
3. Allan, L. N., East, N. J., Mooney, J.T., Sandin, C., “Materials for large far-IR telescope mirrors,” Proc. SPIE 10698, Paper 10698-58 (2018).
4. Dipierro, M. et al., “The Origins Space telescope cryogenic-thermal architecture,” Proc. SPIE 10698, Paper 10698-44 (2018).
5. Sakon, I., et al., “The mid-infrared imager/spectrometer/coronagraph instrument (MISC) for the Origins Space Telescope,” Proc. SPIE 10698, Paper 10698-42 (2018).
6. Staguhn, J. G., et al., “Origins Space Telescope: the far infrared imager and polarimeter FIP,” Proc. SPIE 10698, Paper 10698-45 (2018).
7. Risacher, C. et al., “The upGREAT 1.9 THz multi-pixel high resolution spectrometer for the SOFIA Observatory,” A&A 595, A34 (2016). How about TST paper?
8. Goldsmith, P., Sub--Millimeter Heterodyne Focal-Plane Arrays for High-Resolution Astronomical Spectroscopy,'' Goldsmith, P. 2017, The Radio Science Bulletin, 362, 53.
9. Performance of Backshort-Under-Grid Kilopixel TES arrays for HAWC+", DOI 10.1007/s10909-016-1509-9
10. Characterization of Kilopixel TES detector arrays for PIPER", Bibliographic link: http://adsabs.harvard.edu/abs/2018AAS...23115219D [187]
11. A Time Domain SQUID Multiplexing System for Large Format TES Arrays": https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=31361     [188]
12. Mellberg, A., et al, “InP HEMT-Based,Cryogenic, Wideband LNAs for 4-8 GHz operating at very low DC Power”, https://ieeexplore.ieee.org/document/1014467 [189]
13. Montazeri, S. et al, “A Sub-milliwatt 4-8 GHz SiGe Cryogenic Low Noise Amplifier, https://ieeexplore.ieee.org/document/8058937 [190]
    and
14. Montazeri, S. et al, “Ultra-Low-Power Cryogenic SiGe Low-Noise Amplifiers: Theory and Demonstration” , IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 64, NO. 1, JANUARY 2016.

Schleeh, J. et al, “Ultralow-Power Cryogenic InP HEMT with Minimum Noise Temperature of 1 K at 6 GHz”, IEEE ELECTRON DEVICE LETTERS, VOL. 33, NO. 5, MAY 2012.

Desired Deliverables of Phase II

Prototypes and analysis

Desired Deliverables Description

• All of the detectors and associated readout and other technologies can be built as prototypes to advance TRL.  Detailed analysis of the operation and tradeoff space would also be very helpful.

State of the Art and Critical Gaps

Efficient multi-pixel readout electronics are needed both for room temperature operation as well as cryogenic temperatures. We can produce millions-of-pixel detector arrays at infrared wavelengths up to about 14 microns, only because there are readout circuits (ROIC) available on the market. Without these, high-density, large-format infrared arrays such as Quantum Well Infrared Photodiode, HgCdTe, and Strained Layer Superlattice would not exist. The Moore's Law corollary for pixel count describes the number of pixels for the digital camera industry as growing in an exponential manner over the past several decades, and the trend is continuing. The future of long-wave detectors is moving toward tens of thousands of pixels and beyond. Readout circuits capable of addressing their needs do not exist, and without them the astronomical community will not be able to keep up with the needs of the future. These technology needs must be addressed now, or we are at risk of being unable to meet the science requirements of the future.

• Commercially available readout integrated circuits (ROICs) typically have well depths of less than 10 million electrons.
• 6-9bit, ROACH-2 board solutions with 2000 bands, <10kHz bandwidth in each are SOA.
• IR detector systems are needed for Earth imaging based on the recently release Earth Decadal Survey.
• Direct detectors with D~10^9 cm-rtHz/W achieved in this range. Technologies with new materials that take advantage of cooling to the 30-100K range are capable of D~10^12 cm-rtHz/W. Broadband (>15%) heterodyne detectors that can provide sensitivities of 5 to 10 times the quantum limit in the submillimeter-wave range while operating at 30-77 K are an improvement in the state or art due to higher operating temperature.
• Detector array detection efficiency < 20% at 532nm (including fill factor and probability of detection) for low after pulsing, low dead time designs is SOA.
• Far-IR bolometric heterodyne detectors are limited to 3dB gain bandwidth of around 3 GHz. Novel superconducting material such a MgB2 can provide significant enhancement of up to 9 GHz IF bandwidth.
• Cryogenic Low Noise Amplifiers (LNAs) in the 4-8 GHz bandwidth with thermal stability are needed for Focal Plane Arrays, Origins Space Telescope (OST) instruments, Origins Survey Spectrometers (OSS), microwave kinetic inductance detectors (MKIDs), Far-infrared Imager and Polarimeters (FIP), Heterodyne Instrument on OST (HERO), and the Lynx Telescope. DC power dissipation should be only a few mW.
• Another frequency range of interest for LNAs is 0.5-8.5 GHz. This is useful for Heterodyne Receiver for OST (HERO). Other NASA systems in the Space Geodesy Project (SGP) would be interested in bandwidths up to 2-14 GHz.
• 15-20 dB Gain and <5 Kelvin Noise over the 4-8 GHz bandwidth has been demonstrated.
• -Currently, all space borne heterodyne receivers are single pixel. Novel architectures are needed for ~100 pixel arrays at 1.9 THz
• The current State of the Art readout circuit is capable of reading one TES per pixel in a 1 mm square area. 2D arrays developed by NIST have been a boon for current NASA programs. However, NIST has declined to continue to produce two-dimensional circuits, or to develop one capable of two TES-per-pixel readout. This work is extremely important to NASA’s filled, kilopixel bolometer array program.
• Two dimensional cryogenic readout circuits are analogous to semiconductor Readout Integrated Circuits operating at much higher temperatures. We can produce millions-of-pixel detector arrays at infrared wavelengths up to about 14 microns, only because there are readout circuits (ROIC) available on the market. Without these, high-density, large-format infrared arrays such as Quantum Well Infrared Photodiode, HgCdTe, and Strained Layer Superlattice would not exist.
• For Lidar detectors, extended wavelength InGaAs detector/preamplifier packages operating at 2-2.1 micron wavelengths with high quantum efficiency (> 90%) operating up to about 1 GHz bandwidth are available as are packages operating up to about 10 GHz with lower quantum efficiency.  Detectors that have > 90% quantum efficiency over the full bandwidth from near DC to > 5 GHz and capable of achieving near-shot-noise limited operation are not currently available.

Relevance / Science Traceability

• Future short-wave, mid-wave, and long-wave infrared Earth science and planetary science missions all require detectors that are sensitive and broadband with low power requirements.
• Future Astrophysics instruments require cryogenic detectors that are super-sensitive and broadband and provide imaging capability (multi-pixel).
• Aerosol spaceborne lidar as identified by 2017 decadal survey to reduce uncertainty about climate forcing in aerosol-cloud interactions and ocean ecosystem carbon dioxide uptake. Additional applications in planetary surface mapping, vegetation, and trace gas lidar.
• Earth Radiation Budget measurement per 2007 decadal survey Clouds and Earth’s Radiant Energy System (CERES) Tier-1 designation to maintain the continuous radiation budget measurement for climate modeling and better understand radiative forcings.
• Astrophysical missions such as Origins Space Telescope (OST) will need IR and Far-IR detector and related technologies.
• LANDSAT Thermal InfraRed Sensor (TIRS), Climate Absolute Radiance and Refractivity Observatory (CLARREO), BOReal Ecosystem Atmosphere Study (BOREAS), Methane Trace Gas Sounder or other infrared earth observing missions.
• Current Science missions utilizing two-dimensional, large-format cryogenic readout circuits:
  (1) HAWC + (High Resolution Airborne Wideband Camera Upgrade) for SOFIA (Stratospheric Observatory for Infrared Astronomy)Future missions:

1)     PIPER (Primordial Inflation Polarization Experiment), Balloon-borne

2)     PICO (Probe of Inflation and Cosmic Origins, a Probe-class Cosmic Microwave Background mission concept

• Lidar detectors are needed for 3D wind measurements from space.

Scope Title
Detectors

Scope Description

This subtopic covers detector requirements for a broad range of wavelengths from ultraviolet (UV) through to gamma ray for applications in Astrophysics, Earth Science, Heliophysics, and Planetary Science. Requirements across the board are for greater numbers of readout pixels, lower power, faster readout rates, greater quantum efficiency, single photon counting, and enhanced energy resolution.

The proposed efforts must be directly linked to a requirement for a NASA mission. These include Explorers, Discovery, Cosmic Origins, Physics of the Cosmos, Solar-Terrestrial Probes, Vision Missions, and Earth Science Decadal Survey missions. Proposals should reference current NASA missions and mission concepts where relevant. Specific technology areas are:

• Large-format, solid-state single photon counting radiation tolerant detectors in charge-coupled device (CCD) or Complementary metal-oxide-semiconductor (CMOS) architecture, including 3D stacked architecture, for astrophysics, planetary, and UV heliophysics missions
• Solid-state detectors with polarization sensitivity relevant to astrophysics as well as planetary and Earth science applications for example in spectropolarimetry
• Significant improvement in wide band gap semiconductor materials (such as AlGaN, ZnMgO and SiC), individual detectors and detector arrays for astrophysics missions and planetary science composition measurements. For example, SiC Avalanche Photodiodes (APDs) must show: EUV photon counting, a linear mode gain > 10E6 at a breakdown reverse voltage between 80 and 100 V; detection capability of better than 6 photons/pixel/s down to 135 nm wavelength. See needs of National Research Council's Earth Science Decadal Survey (NRC, 2007): Tropospheric ozone.
• Solar-blind (visible-blind) UV, far-UV (80-200 nm), EUV sensor technology with high pixel resolution, large format, high sensitivity and high dynamic range, low voltage and power requirements; with or without photon counting.
• UV detectors suitable for upcoming Ultrahigh-Energy Cosmic Ray (UHECR) mission concepts
• Solar X-ray detectors with small independent pixels (<250 µm) and fast read-out (>10,000 count/s/pixel) over an energy range from <5 keV to 300 keV.
• Supporting technologies that would help enable X-ray Surveyor mission that requires the development of X-ray microcalorimeter arrays with much larger field of view, ~10⁵-10⁶ pixels, of pitch ~25-100 µm, and ways to read out the signals. For example, modular superconducting magnetic shielding is sought that can be extended to enclose a full-scale focal plane array. All joints between segments of the shielding enclosure must also be superconducting.
• Improved long-wavelength blocking filters are needed for large-area, X-ray microcalorimeters. Filters with supporting grids are sought that, in addition to increasing filter strength, also enhance EMI shielding (1 - 10 GHz) and thermal uniformity for decontamination heating. X-ray transmission of greater than 80% at 600 eV per filter is sought, with infrared transmissions less than 0.01% and ultraviolet transmission of less than 5% per filter. Means of producing filter diameters as large as 10 cm should be considered.
• Detectors with fast readout that can support high count rates and large incident flux from the extreme UV (EUV) and X-Rays for heliophysics applications, especially solar-flare measurements.

References

• About Cosmic Origins (COR): https://cor.gsfc.nasa.gov/ [192]
• Planetary Missions Program Office: https://planetarymissions.nasa.gov/ [193]
• Explorers and Heliophysics Projects Division (EHPD): https://ehpd.gsfc.nasa.gov/ [194]
• NASA Astrophysics Roadmap: https://smd-prod.s3.amazonaws.com/science-red/s3fs-public/atoms/files/secure-Astrophysics_Roadmap_2013_0.pdf [195]
• NASA Heliophysics Roadmap: https://smd-prod.s3.amazonaws.com/science-red/s3fs-public/atoms/files/2014_HelioRoadmap_Final_Reduced_0.pdf [196]
• "Vision and Voyages for Planetary Science in the Decade 2013-2022": http://solarsystem.nasa.gov/2013decadal/ [197]

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Research

Desired Deliverables Description

Results of tests and analysis of designs and/or prototype hardware. Hardware for further testing and evaluation.

State of the Art and Critical Gaps

This subtopic aims to develop and advance detector technologies focused on ultraviolet, x-ray, gamma ray spectral range. The science needs in this range spans a number of fields with main focus on astrophysics, planetary science, and UV heliophysics. A number of solid-state detector technologies promise to surpass the traditional image-tube based detectors. Silicon-based detectors leverage enormous investments and promise high performance detectors while more complex material such as gallium nitride and silicon carbide offer intrinsic solar blind response. This subtopic supports efforts to advance technologies that significantly improve the efficiency, dynamic range, noise, radiation tolerance, spectral selectivity, reliability, and manufacturability in detectors.

Relevance / Science Traceability

Flagship missions under study: Large Ultraviolet Optical Infrared Surveyor (LUVOIR), Habitable Exoplanet Observatory (HabEx), Lynx, New Frontier-IO,

• Luvoir - Large UV/Optical/IR Surveyor: https://asd.gsfc.nasa.gov/luvoir/ [198]
• Habitable Exoplanet Observatory (HabEx): https://www.jpl.nasa.gov/habex/ [199]
• The LYNX Mission Concept: https://wwwastro.msfc.nasa.gov/lynx/ [200]
• NASA Astrophysics: https://science.nasa.gov/astrophysics/ [201]
• The Explorers Program: https://explorers.gsfc.nasa.gov/ [202]

Scope Description:

The 2013 National Research Council’s, Solar and Space Physics: A Science for a Technological Society (http://nap.edu/13060 [204]) motivates this subtopic: “Deliberate investment in new instrument concepts is necessary to acquire the data needed to further solar and space physics science goals, reduce mission risk, and maintain an active and innovative hardware development community.” This subtopic solicits development of advanced in-situ instrument technologies and components suitable for deployment on heliophysics missions. Advanced sensors for the detection of elementary particles (atoms, molecules and their ions) and electric and magnetic fields in space and associated instrument technologies are often critical for enabling transformational science from the study of the sun's outer corona, to the solar wind, to the trapped radiation in Earth's and other planetary magnetic fields, and to the atmospheric composition of the planets and their moons. These technologies must be capable of withstanding operation in space environments, including the expected pressures, radiation levels, launch and impact stresses, and range of survival and operational temperatures. Technology developments that result in a reduction of mass, power, volume, and data rates for instruments and instrument components without loss of scientific capability are of particular importance. In addition, technologies that can increase instrument resolution and sensitivity or achieve new and innovative scientific measurements are solicited. Improvements in particles and fields sensors and associated instrument technologies enable further scientific advancement for upcoming NASA missions such as CubeSats, Explorers, Solar Terrestrial Probe (STP), Living With a Star (LWS), and planetary exploration missions. 

Specifically, this subtopic solicits instrument development that provides significant advances in the following areas:

• Mini scalar-only temperature insensitive absolute magnetometer for CubeSats
• Magnetically clean >2 meter compact deployable booms for CubeSats
• Complementary metal-oxide-semiconductor (CMOS) active pixel type or charge-coupled device (CCD) type electron detectors in the energy range ~0.1-20KeV
• Fast visible light CMOS or CCD imaging detectors for high sensitivity (10 photons per pixel) read out of scintillator crystal light tracks caused by incident neutrons or protons
• Wide energy fast particle detectors resistant to very high radiation of >100Mrads, for instance diamond detectors.
• Grids, collimators and other components that enable the rejection of stray UV or visible light
• Innovative high efficiency neutral particle ionizers based on thermionic, cold electron emission or UV ionization
• Direct neutral particle detectors to energies <1eV
• High-resolution and high-efficiency UV-blind ENA detectors
• High voltage space qualified optocoupler components for >20KV power supplies
• Innovative miniature nested electrostatic analyzers for scan-less energy analysis
• Detectors/sensors for interplanetary/interstellar dust detection
  • Electronics technologies (e.g., field programmable gate array (FPGA) and application-specific integrated circuit (ASIC) implementations, advanced array readouts, miniature high voltage power supplies)

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

References:

For example missions, see http://science.nasa.gov/missions [205]. (E.g. NASA Magnetospheric Multiscale (MMS) mission, Fast Plasma Instrument)
For details of the specific requirements see the National Research Council’s, Solar and Space Physics: A Science for a Technological Society (http://nap.edu/13060 [204]).

Expected TRL or TRL range at completion of the project: 3-6

Desired Deliverables of Phase II (Check all that apply):

Prototype, Hardware

Desired Deliverables Description:

A prototype component that can be tested in engineering model instruments.

State of the Art and Critical Gaps:

In situ particles and fields instruments and technologies are essential bases to achieve the Science Mission Directorate's (SMD) Heliophysics goals summarized in the National Research Council’s, Solar and Space Physics: A Science for a Technological Society. These technologies play indispensable roles for NASA’s LWS and STP mission programs, as well as a host of smaller spacecraft in the Explorers Program. In addition, there is growing demand for particles and fields instrumentation amenable to CubeSats and SmallSats. To narrow the critical gaps between the current state of art and the technology needed for the ever-increasing science/exploration requirements, in-situ technologies are being sought to achieve much higher resolution and sensitivity with significant improvements over existing capabilities, and at the same time with lower mass, power and volume.

Relevance / Science Traceability:

Particles and fields instruments and technologies are essential bases to achieve SMD's Heliophysics goals summarized in the National Research Council’s, Solar and Space Physics: A Science for a Technological Society. In situ instruments and technologies play indispensable roles for NASA’s LWS and STP mission programs, as well as a host of smaller spacecraft in the Explorers Program. In addition, there is growing demand for particles and fields technologies amenable to CubeSats and SmallSats. NASA SMD has two excellent programs to bring this subtopic technologies to higher level: Heliophysics Instrument Development for Science (H-TIDeS) and Heliophysics Flight Opportunities for Research and Technology (H-FORT). H-TIDeS seeks to advance the development of technologies and their application to enable investigation of key heliophysics science questions. This is done through incubating innovative concepts and development of prototype technologies. It is intended that technologies developed through H-TIDeS would then be proposed to H-FORT to mature by demonstration in a relevant environment. The H-TIDES and H-FORT programs are in addition to Phase III opportunities. Further opportunities through SMD include Explorer Missions, New Frontiers Missions, and the upcoming Geospace Dynamic Constellation.

Scope Description

This subtopic solicits development of advanced instrument technologies and components suitable for deployment on in situ planetary and lunar missions. These technologies must be capable of withstanding operation in space and planetary environments, including the expected pressures, radiation levels, launch and impact stresses, and range of survival and operational temperatures. Technologies that reduce mass, power, volume, and data rates for instruments and instrument components without loss of scientific capability are of particular importance, for both conventional missions as well as for small satellite missions. In addition, technologies that can increase instrument resolution and sensitivity or achieve new & innovative scientific measurements are solicited. For examples of NASA science missions, see https://science.nasa.gov/missions-page [207]. For details of the specific requirements see the National Research Council report "Vision and Voyages for Planetary Science in the Decade 2013-2022" (http://solarsystem.nasa.gov/2013decadal/ [197]), hereafter referred to as the Planetary Decadal Survey). Of particular interest are technologies to support future missions under the New Frontiers and Discovery programs. 

Specifically, this subtopic solicits instrument development that provides significant advances in the following areas, broken out by planetary body:

• Mars - Sub-systems relevant to current in situ instrument needs (e.g., lasers and other light sources from UV to microwave, X-ray and ion sources, detectors, mixers, mass analyzers, etc.) or electronics technologies (e.g., field programmable gate array (FPGA) and application-specfic integrated circuit (ASIC) implementations, advanced array readouts, miniature high voltage power supplies). Technologies that support high precision in situ measurements of elemental, mineralogical, and organic composition of planetary materials are sought. Conceptually simple, low risk technologies for in situ sample extraction and/or manipulation including fluid and gas storage, pumping, and chemical labeling to support analytical instrumentation. Seismometers, mass analyzers, technologies for heat flow probes, and atmospheric trace gas detectors are sought. Improved robustness and g-force survivability for instrument components, especially for geophysical network sensors, seismometers, and advanced detectors (intensified charge-coupled devices (iCCDs), photomultiplier tube (PMT) arrays, etc.). Instruments geared towards rock/sample interrogation prior to sample return.
• Venus - Sensors, mechanisms, and environmental chamber technologies for operation in Venus's high temperature, high-pressure environment with its unique atmospheric composition. Approaches that can enable precision measurements of surface mineralogy and elemental composition and precision measurements of trace species, noble gases and isotopes in the atmosphere.
• Small Bodies - Technologies that can enable sampling from asteroids and from depth in a comet nucleus, improved in situ analysis of comets. Imagers and spectrometers that provide high performance in low light environments. Dust environment measurements and particle analysis, small body resource identification, and/or quantification of potential small body resources (e.g., oxygen, water and other volatiles, hydrated minerals, carbon compounds, fuels, metals, etc.). Advancements geared towards instruments that enable elemental or mineralogy analysis (such as high-sensitivity X-ray and UV-fluorescence spectrometers, UV/fluorescence systems, scanning electron microscopy with chemical analysis capability, mass spectrometry, gas chromatography and tunable diode laser sensors, calorimetry, imaging spectroscopy, and laser-induced breakdown spectroscopy (LIBS).
• Saturn, Uranus, and Neptune - Components, sample acquisition, and instrument systems that can enhance mission science return and withstand the low-temperatures/high-pressures of the atmospheric probes during entry.
• The Moon - This topic seeks advancement of concepts and components to develop a Lunar Geophysical Network as envisioned in the Planetary Decadal Survey. Understanding the distribution and origin of both shallow and deep moonquakes will provide insights into the current dynamics of the lunar interior and its interplay with external phenomena (e.g., tidal interactions with Earth). The network is envisioned to be comprised of multiple free-standing seismic stations which would operate over many years in even the most extreme lunar temperature environments. Technologies to advance all aspects of the network including sensor emplacement, power, and communications in addition to seismic, heat flow, magnetic field and electromagnetic sounding sensors are desired.

Novel instrument concepts are encouraged particularly if they enable a new class of scientific discovery. Technology developments relevant to multiple environments and platforms are also desired. Proposers should show an understanding of relevant space science needs and present a feasible plan to fully develop a technology and infuse it into a NASA mission.

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software

Desired Deliverables Description

In-situ instruments in TRL 3 - 5 for planetary science purpose

State of the Art and Critical Gaps

In situ instruments and technologies are essential bases to achieve Science Mission Directorate's (SMD's) planetary science goals summarized in the Planetary Decadal Survey. In situ instruments and technologies play indispensable role for NASA’s New Frontiers and Discovery missions to various planetary bodies (Mars, Venus, Small Bodies, Saturn, Uranus, Neptune, Moon, etc.).

There are currently various in situ instruments for diverse planetary bodies. However, there are ever increasing science and exploration requirement and challenges for diverse planetary bodies. For example, there is urgent need for exploring RSL (recurring slope lineae) on Mars, plumes from planetary bodies, as well as a growing demand for in situ technologies amenable to small spacecraft.

To narrow the critical gaps between the current state of art and the technology needed for the ever increasing science/exploration requirements, in situ technologies are being sought to achieve much higher resolution and sensitivity with significant improvements over existing capabilities with lower mass, power and volume.

Relevance / Science Traceability

In situ instruments and technologies are essential bases to achieve SMD's planetary science goals summarized in the Planetary Decadal Survey. In situ instruments and technologies play an indispensable role for NASA’s New Frontiers and Discovery missions to various planetary bodies.

In additional to Phase III opportunities, SMD offers several instrument development programs as paths to further development and maturity. These include the Planetary Instrument Concepts for the Advancement of Solar System Observations (PICASSO) Program, which invests in low-TRL technologies and funds instrument feasibility studies, concept formation, proof-of-concept instruments, and advanced component technology, and the Maturation of Instruments for Solar System Exploration (MatISSE) Program, which invests in mid-TRL technologies and enables timely and efficient infusion of technology into planetary science missions.

Scope Description

NASA seeks measurement capabilities that support current satellite and model validation, advancement of surface-based remote sensing networks, and targeted Airborne Science Program and ship-based field campaign activities as discussed in the Research Opportunities in Space and Earth Science (ROSES) solicitation. Data from such sensors also inform process studies to improve our scientific understanding of the Earth System. In-situ sensor systems (airborne, land, and water-based) can comprise stand-alone instrument and data packages; instrument systems configured for integration on ship-based (or alternate surface-based platform) and in-water deployments, NASA’s Airborne Science aircraft fleet or commercial providers, Unmanned Aircraft Systems (UAS), or balloons, ground networks; or end-to-end solutions providing needed data products from mated sensor and airborne/surface/subsurface platforms. An important goal is to create sustainable measurement capabilities to support NASA’s Earth science objectives, with infusion of new technologies and systems into current/future NASA research programs. Instrument prototypes as a deliverable in Phase II proposals and/or field demonstrations are highly encouraged.

Complete instrument systems are generally desired, including features such as remote/unattended operation and data acquisition, and minimum size, weight, and power consumption. All proposals must summarize the current state of the art and demonstrate how the proposed sensor or sensor system represents a significant improvement over the current state of the art.

Specific desired sensors or mated platform/sensors include:

• A hyperspectral radiometry system with polarization capability covering the UV-Vis-NIR wavelength range (350-865 with a minimum resolution of 5 nm; 2.5-nm desired). The instrument shall measure hyperspectral above water upwelling radiance, sky radiance, downwelling irradiance and polarization state of the atmosphere and ocean, and be capable of autonomously positioning itself with respect to the sun for optimized measurement geometry.
• An in situ hyperspectral ocean water absorption instrument (ocean submersible to 300 m) covering the UV-Vis wavelength range (resolution of ≤2nm for 350-750 nm and ≤5nm for 300-350nm) with an accuracy better than 0.005 m^-1 or 5% of the signal and precision better than 0.001 m^-1. Instrument design must mitigate/correct for the confounding effects of scattering and fluorescence.
• In-situ measurements of ocean particulate backscatter, depolarization, beam attenuation, and diffuse attenuation coefficients relevant for combined ocean-atmosphere lidar remote sensing (355, 473, 486, 532, 1064 nm wavelengths and 170-180° scattering angle with ≤1 degree angular resolution).
• In situ polarized hyperspectral UV-Vis volume scattering function (VSF) instrument (ocean submersible to 300 m) covering the angular range close to 0 degrees and, more importantly so, as far as 180 degrees (with  ≤2 degree angular resolution). Instrument should have ability to measure (at least) horizontal and vertical aspects of linear polarization. Degree of resolution in angles and wavelength can be decreased for instrument portability and robustness (such as for autonomous underwater vehicle (AUV) deployments).
• Portable hyperspectral UV-Vis-NIR radiometric calibration system with a stabilized optical light source for verification of field radiometer stability by traceable NIST standards with variable flux levels. System must include thermal stabilization for the instrument to be independent of ambient temperature for evaluation of radiometric stability as function of time.
• Innovative, high-value sensors directly targeting a stated NASA need (including aerosols and trace gases) may also be considered. Proposals must identify a specific, relevant NASA subject matter expert.

Expected TRL or TRL range at completion of the project is: 4 to 7

Desired Deliverables of Phase II: Prototype, Hardware, and/or Software

Desired Deliverables Description: The ideal Phase II effort would build, characterize, and deliver a prototype instrument to NASA including necessary hardware and operating software. The prototype would be fully-functional, but the packaging may be more utilitarian (i.e., less polished) than a commercial model.

State of the Art and Critical Gaps

The S1.08 subtopic is and remains highly relevant to NASA Science Mission Directorate (SMD) and Earth Science research programs, in particular the Earth Science Atmospheric Composition, Climate Variability & Change, and Carbon Cycle and Ecosystems focus areas. In situ and ground-based sensors inform NASA ship and airborne science campaigns led by these programs and provide important validation of the current and next-generation of satellite-based sensors (e.g., PACE, OCO-2, TEMPO, SGB, and A-CCP – see links in references). The solicited measurements will be highly relevant to current and future NASA campaigns with objectives and observing strategies similar to past campaigns, e.g., NAAMES, EXPORTS, CAMP2EX, FIREX-AQ, KORUS-AQ, DISCOVER-AQ (see links in references).

References:

Relevant current and past satellite missions and field campaigns include:

PACE Satellite Mission, scheduled to launch in 2022 that focuses on observations of ocean biology, aerosols, and clouds (https://pace.gsfc.nasa.gov/ [209])

Decadal Survey Recommended ACCP Mission focusing on aerosols, clouds, convection, and precipitation/Aerosols and Clouds, Convection and Precipitation (ACCP) (combined) (https://science.nasa.gov/earth-science/decadal-surveys [210])

Decadal Survey Recommended SGB Mission focusing on surface biology and geology/ Surface Biology and Geology (https://science.nasa.gov/earth-science/decadal-surveys [210])

OCO-2 Satellite Mission that targets spaceborne observations of carbon dioxide and the Earth’s carbon cycle (https://www.nasa.gov/mission_pages/oco2/index.html [211])

TEMPO Satellite Mission focusing on geostationary observations of air quality over North America (http://tempo.si.edu/overview.html [212])

NAAMES Earth Venture Suborbital field campaign targeting the North Atlantic phytoplankton bloom cycle and impacts on atmospheric aerosols, trace gases, and clouds (https://naames.larc.nasa.gov [213])

EXPORTS field campaign targeting the export and fate of upper ocean net primary production using satellite observations and surface-based measurements (https://oceanexports.org [214])

CAMP2Ex airborne field campaign focusing on tropical meteorology and aerosol science (https://espo.nasa.gov/camp2ex [215])

FIREX-AQ airborne and ground-based field campaign targeting wildfire and agricultural burning emissions in the United States (https://www.esrl.noaa.gov/csd/projects/firex-aq/ [216])

AToM airborne field campaign mapping the global distribution of aerosols and trace gases from pole-to-pole (https://espo.nasa.gov/atom/content/ATom [217])

KORUS-AQ airborne and ground-based field campaign focusing on pollution and air quality in the vicinity of the Korean Peninsula (https://espo.nasa.gov/korus-aq/content/KORUS-AQ [218])

DISCOVER-AQ airborne and ground-based campaign targeting pollution and air quality in four areas of the United States (https://discover-aq.larc.nasa.gov/ [219])

Scope Title

Low temperature/high efficiency cryocoolers

Scope Description

NASA seeks improvements to multistage low temperature spaceflight cryocoolers. Coolers are sought with the lowest temperature stage typically in the range of 4 to 10 K, with cooling power at the coldest stage larger than currently available, and high efficiency. The desired cooling power is application specific, but two examples are 0.3 Watts at 10 K and 0.2 Watts at 4 K. Devices that produce extremely low vibration, particularly at frequencies below a few hundred Hz, are of special interest. System or component level improvements that improve efficiency and reduce complexity and cost are desirable.

Expected TRL or TRL range at completion of the project: 2 to 5

Desired Deliverables of Phase II:

Prototype Hardware

Desired Deliverables Description

Functioning hardware ready for functional and possibly environmental testing.

State of the Art and Critical Gaps

Current spaceflight cryocoolers for this temperature range include linear piston driven Stirling cycle or pulse tube cryocoolers with Joule-Thompson low temperature stages. One such state-of-the-art cryocooler provides 0.09 W of cooling at 6 K. For large future space observatories, large cooling power and much greater efficiency will be needed. For cryogenic instruments or detectors on instruments with tight point requirements, orders of magnitude improvement in the levels of exported vibration will be required.

Some of these requirements are laid out in the "Advanced cryocoolers" Technology gap in the latest (2017) Cosmic Origins Program Annual Technology Report.

Relevance / Science Traceability

Science traceability: Goal 1 and Objective 1.6 of NASA’s Strategic Plan:

• Goal 1: Expand the frontiers of knowledge, capability, and opportunity in space
  • Objective 1.6: Discover how the universe works, explore how it began and evolved, and search for life on planets around other stars.

Low temperature cryocoolers are listed as a "Technology Gap" in the latest (2017) Cosmic Origins Program Annual Technology Report.

Future missions that would benefit from this technology include two of the large missions under study for the 2020 Astrophysics Decadal Survey:

• Origins Space Telescope
• Lynx microcalorimeter instrument

References

For more information on the Origins Space Telescope, see:
https://asd.gsfc.nasa.gov/firs/ [221]

Scope Title
Actuators and other cryogenic devices

Scope Description

NASA seeks devices for cryogenic instruments, including:

• Small, precise motors and actuators, preferably with superconducting windings, that operate with extremely low power dissipation.  Devices using standard NbTi conductors, as well as devices using higher temperature superconductors that can operate above 5 K, are of interest.
• Cryogenic heat pipes for heat transport within instruments.  Heat pipes using hydrogen, neon, oxygen, argon, and methane are of interest.  Length should be at least 0.3 m.

Expected TRL or TRL range at completion of the project: 3 to 4

Desired Deliverables of Phase II:

Prototype Hardware

Desired Deliverables Description

Working prototypes ready for testing in the relevant environments are desired.

State of the Art and Critical Gaps

Motors and actuators: Instruments often have motors and actuators, typically for optical elements.  In current cryogenic instruments, these devices often dissipate relatively large powers and are a significant design drivers.

Cryogenic heat pipes: Currently, heat transport in cryogenic instruments are handled with solid thermal straps.  These do not scale well for larger heat loads.

Relevance / Science Traceability

Science traceability:
NASA Strategic plan 2018, Objective 1.1: Understand The Sun, Earth, Solar System,
And Universe

Almost all instruments have motors and actuators for changing filters, adjusting focus, scanning, and other functions.  On low temperature instruments, for example on mid- to far-IR observatories, dissipation in actuators can be a significant design problem.

References

For more information on earlier low temperature heat pipes, see

• Brennen, et al. AIAA paper 93-2735,  https://doi.org/10.2514/6.1993-2735 [222]
• Prager, R.C., AIAA paper 80-1484,  https://doi.org/10.2514/6.1980-1484 [223]
• Alario, J. and Kosson, R. AIAA paper 80-0212,  https://doi.org/10.2514/6.1980-212 [224]

Scope Title
Ultra-Lightweight Dewars

Scope Description

NASA seeks extremely lightweight thermal isolation systems for scientific instruments. An important example is a large cylindrical, open top dewar to enable large, cold balloon telescopes. In one scenario, such a dewar would be launched warm, and so would not need to function at ambient pressure, but at altitude, under ~4 millibar external pressure, it would need to contain cold helium vapor.  The ability to rapidly pump and hold a vacuum at altitude is necessary. An alternative concept is that the dewar would be launched at operating temperature, with some or all of the needed liquid helium.  In both cases, heat flux through the walls should be less than 0.5 Watts per square meter, and the internal surfaces must be leak tight against superfluid helium. Initial demonstration units of greater than 1 meter diameter and height are desired, but the technology must be scalable to an inner diameter of 3 – 4 meters with a mass that is a small fraction of the net lift capability of a scientific balloon (~2000 kg).

Expected TRL or TRL range at completion of the project: 3 to 4

Desired Deliverables of Phase II:

Prototype Hardware

Desired Deliverables Description

A working prototype of the scale described is desired.

State of the Art and Critical Gaps

Currently available liquid helium dewars have heavy vacuum shells that allow them to be operated in ambient pressure. Such dewars have been used for balloon-based astronomy, as in the Absolute Radiometer for Cosmology, Astrophsyics, and Diffuse Emission (ARCADE) experiment. However, the current dewars are already near the limit of balloon lift capacity, and cannot be scaled up to the required size for future astrophysics measurements.

Relevance / Science Traceability

Science traceability: NASA Strategic plan 2018, Objective 1.1: Understand the Sun, Earth, Solar System, and Universe.

The potential for ground-based infrared astronomy is extremely limited. Even in airborne observatories, such as SOFIA, observations are limited by the brightness of the atmosphere and the warm telescope itself. However, high altitude scientific balloons are above enough of the atmosphere that, with a telescope large enough and cold enough, background-limited observations are possible. The ARCADE project demonstrated that at high altitudes, it is possible to cool instruments in helium vapor. Development of ultra-lightweight dewars that could be scaled up to large size, yet still be liftable by a balloon would enable ground-breaking observational capability.

References

For a description of a state-of-the art balloon cryostat, see
Singal, et al. "The ARCADE 2 instrument," The Astrophysical Journal, 730:138 (12pp), 2011 April 1

Scope Title
Miniaturized/Efficient Cryocooler Systems

Scope Description

NASA seeks miniature, highly efficient cryocoolers for instruments on earth and planetary missions. A range of cooling capabilities sought. Two examples include 0.2 Watt at 30 K with heat rejection at 300 K, and 0.3 W at 35K with heat reject of 150 K. For both examples, an input power of ≤ 5 Watt and a total mass of ≤ 400 grams is desired. The ability to fit within the volume and power limitations of a SMALLSAT platform would be highly advantageous. Components, such as low-cost cryocooler electronics that are sufficiently rad hard for lunar or planetary missions, are also sought.

Expected TRL or TRL range at completion of the project: 2 to 4

Desired Deliverables of Phase II:

Prototype Hardware

Desired Deliverables Description

Desired deliverables include miniature coolers and components, such as electronics, that are ready for functional and environmental testing.

State of the Art and Critical Gaps

Present state of the art capabilities provide 0.1 W of cooling capacity with heat rejection at 300 K at approximately 5 W input power with a system mass of 400 grams.

Cryocoolers enable the use of highly sensitive detectors, but current coolers cannot operate within the tight power constraints of outer planetary missions. Cryocooler power could be greatly reduced by lowering the heat rejection temperature, but presently there are no spaceflight systems that can operate with a heat rejection temperature significantly below ambient.

Relevance / Science Traceability

Science traceability: NASA Strategic plan 2018, Objective 1.1: Understand the Sun, Earth, Solar System, and Universe.

NASA is moving toward the use of small, low cost satellites to achieve many of its Earth science, and some of its planetary science goals. The development of cryocoolers that fit within the size and power constraints of these platforms will greatly expand their capability, for example, by enabling the use of infrared detectors.

In planetary science, progress on cryogenic coolers will enable the use of far- to mid-infrared sensors with orders of magnitude improvement in sensitivity for outer planetary missions. These will allow thermal mapping of outer planets and their moons.

References

An example of cubesat mission using cryocoolers is given at: https://www.jpl.nasa.gov/cubesat/missions/ciras.php [225]

Scope Title
Sub-Kelvin Cooling Systems

Scope Description

Future NASA missions will require requiring sub-Kelvin coolers for extremely low temperature detectors. Systems are sought that will provide continuous cooling with high cooling power (> 5 microWatts at 50 mK), low operating temperature (<35 mK), and higher heat rejection temperature (preferably > 10K), while maintaining high thermodynamic efficiency and low system mass.

Improvements in components for adiabatic demagnetization refrigerators are also sought. Specific components include:

1)     Compact, lightweight, low current superconducting magnets capable of producing a field of at least 4 Tesla while operating at a temperature of at least 10 K, and preferably above 15 K. Desirable properties include:

• A high engineering current density (including insulation and coil packing density), preferably > 300 Amp/mm^2.
• A field/current ratio of >0.33 Tesla/Amp, and preferably >0.66 Tesla/Amp.
• Low hysteresis heating.

2)     Lightweight Active/Passive magnetic shielding (for use with 4 Tesla magnets) with low hysteresis and eddy current losses, and low remanence. Also needed are lightweight, highly effective outer shields that reduce the field outside an entire multi-stage device to < 5 microTesla. Outer shields must operate at 4 - 10 K, and must have penetrations for low temperature, non-contacting heat straps.

3)     Heat switches with on/off conductance ratio > 30,000 and actuation time of <10 s. Materials are also sought for gas gap heat switch shells: these are tubes with extremely low thermal conductance below 1 K; they must be impermeable to helium gas, have high strength, including stability against buckling, and have an inner diameter > 20 mm.

4)     High cooling power density magnetocaloric materials, especially single crystals with volume > 20 cc. Examples of desired single crystals include GdF3, GdLiF4, and Gd elpasolite.

5)     10 mK- 300 mK high resolution thermometry.

6)     Suspensions with the strength and stiffness of Kevlar, but lower thermal conductance from 4 K to 0.050 K.

References

For a description of the state-of-the-art subKelvin cooler in the Hitomi mission, see:
Shirron, et al. "Thermodynamic performance of the 3-stage ADR for the Astro-H Soft-X-ray Spectrometer instrument," Cryogenics 74 (2016) 24–30, and references therein.

For articles describing magnetic subKelvin coolers and their components, see the July 2014 special issue of Cryogenics: Cryogenics 62 (2014) 129–220.

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

Expected TRL or TRL range at completion of the project: 2 to 4

Desired Deliverables of Phase II:

Prototype Hardware

Desired Deliverables Description

For components, functioning hardware that is directly usable in NASA systems is desired.

State of the Art and Critical Gaps

The adiabatic demagnetization refrigerator in the Soft X-ray Spectrometer instrument on the Hitomi mission represents the state of the art in spaceflight sub-Kelvin cooling systems. The system is a 3 stage, dual-mode device. In the more challenging mode, it provides 650 µW of cooling at 1.625 K, while simultaneously absorbing 0.35 µW from a small detector array at 0.050 K. It rejects heat at 4.5 K. In this mode, the detector is held at temperature for 15.1 hour periods, with a 95% duty cycle. Future missions with much larger pixel count will require much higher cooling power at 0.050 K or lower, higher cooling power at intermediate stages, and 100% duty cycle. Heat rejection at a higher temperature is also needed to enable the use of a wider range of more efficient cryocoolers.

Relevance / Science Traceability

Science traceability: Science traceability:
NASA Strategic plan 2018, Objective 1.1: Understand The Sun, Earth, Solar System,
And Universe.

SubKelvin coolers are listed as a "Technology Gap" in the latest (2017) Cosmic Origins Program Annual Technology Report.

Future missions that would benefit from this technology include two of the large missions under study for the 2020 Astrophysics Decadal Survey:

• Origins Space Telescope
• Lynx (microcalorimeter instrument)

Also: Probe of Inflation and Cosmic Origins

Scope Description

Recent developments of laser control and manipulation of atoms have led to new types of precision inertial force and gravity sensors based on atom interferometry. Atom interferometers exploit the quantum mechanical wave nature of atomic particles and quantum gases for sensitive interferometric measurements. Ground-based laboratory experiments and instruments have already demonstrated beyond the state-of-the-art performances of accelerometer, gyroscope, and gravity measurements. The microgravity environment in space provides opportunities for further drastic improvements in sensitivity and precision. Such inertial sensors will have great potential to provide new capabilities for NASA Earth and planetary gravity measurements, for spacecraft inertial navigation and guidance, and for gravitational wave detection and test of properties of gravity in space.

Currently the most mature development of atom interferometers as measurement instruments are those based on light pulsed atom interferometers with freefall cold atoms. There remain a number of technical challenges to infuse this technology in space applications. Some of the identified key challenges are (but not limited to):

• Compact high flux ultra-cold atom sources for free space atom interferometers (Example: >1e+06 total useful free-space atoms, <1 nK, Rb, K, Cs, Yb, Sr, and Hg. Performance and species can be defined by offeror. Other related innovative methods and components for cold atom sources are of great interest, such as a highly compact and regulatable atomic vapor cell.
• Ultra-high vacuum technologies that allow completely sealed, non-magnetic enclosures with high quality optical access and the base pressure maintained
• <1e-09 Torr. Consideration should be given to the inclusion of cold atom sources of interest.
• Beyond the state-of-the-art photonic components at wavelengths for atomic species of interest, particularly at Near Infrared (NIR) and visible: efficient acousto-optic modulators (low RF power ~200 mW, low thermal distortion, ~80% or greater diffraction efficiency); efficient electro-optic modulators (low bias drift, residual AM, and return loss, fiber- coupled preferred), miniature optical isolators (~30 dB isolation or greater, ~ -2 dB loss or less), robust high-speed high-extinction shutters (switching time < 1 ms, extinction > 60 dB are highly desired).
• Flight qualifiable lasers or laser systems of narrow linewidth, high tunability, and/or higher power for clock and cooling transitions of atomic species of interest. Cooling and trapping lasers: 10 kHz linewidth and ~ 1 W or greater total optical power.
• Compact clock lasers: 5e-15 Hz/tau^½ near 1 s (wavelengths for Yb+, Yb, Sr clock transitions are of special interest).

All proposed system performances can be defined by offeror with sufficient justification. Subsystem technology development proposals should clearly state the relevance, define requirements, relevant atomic species and working laser wavelengths, and indicate its path to a space-borne instrument.

References

• 2017 NASA Strategic Technology Investment Plan: https://go.usa.gov/xU7sE [123]
• 2015 NASA Technology Roadmaps: https://go.usa.gov/xU7sy [124]
• NOTE: The 2015 NASA Technology Roadmaps will be replaced beginning early fall of 2019 with the 2020 NASA Technology Taxonomy and the NASA Strategic Technology Integration Framework.  The 2015 NASA Technology Roadmaps will be archived and remain accessible via their current Internet address as well as via the new 2020 NASA Technology Taxonomy Internet page.

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Hardware

Desired Deliverables Description

Prototype hardware, documented evidence of delivered TRL (test report, data, etc.), summary performance analysis, supporting documentation.

State of the Art and Critical Gaps

This technology reduces gravitational sensors from two satellites to a single, table-top instrument and enhances the sensitivity of the state-of-the-art, including time measurement accuracy by factor of 100+.

Relevance / Science Traceability

Currently, no technology exists that can compete with the (potential) sensitivity, (potential) compactness, and robustness of Atom Optical-based gravity and time measurement devices. Earth science, planetary science, and astrophysics all benefit from unprecedented improvements in gravity and time measurement. Specific roadmap items supporting science instrumentation include, but are not limited to:

• TA-7.1.1: Destination Reconnaissance, Prospecting, and Mapping (gravimetry)
• TA-8.1.2: Electronics (reliable control electronics for laser systems)
• TA-8.1.3: Optical Components (reliable laser systems)
• TA-8.1.4: Microwave, Millimeter, and Submillimeter-Waves (ultra-low noise microwave output when coupled w/ optical frequency comb)
• TA-8.1.5: Lasers (reliable laser system w/ long lifetime)

See note in References section regarding the status of the 2015 NASA Technology Roadmaps.

Scope Description

This subtopic solicits development of in-situ instrument technologies and components to advance the maturity of science instruments and plume sample collection systems focused on the detection of evidence of life, especially extant life, in the Ocean Worlds (e.g., Europa, Enceladus, Titan, Ganymede, Callisto, Ceres, etc.). Technologies that can increase instrument resolution and sensitivity or achieve new and innovative scientific measurements are of particular interest. Technologies that allow collection during high speed (>1 km/sec) velocity passes through a plume are solicited as are technologies that can maximize total sample mass collected while passing through tenuous plumes. This fly-through sampling focus is distinct from S4.02, which solicits sample collection technologies from surface platforms.

These technologies must be capable of withstanding operation in space and planetary environments, including the expected pressures, radiation levels, launch and impact stresses, and range of survival and operational temperatures. Technologies that reduce mass, power, volume, and data rates for instruments and instrument components without loss of scientific capability are of particular importance. 

Specifically, this subtopic solicits instrument technologies and components that provide significant advances in the following areas, broken out by planetary body:

• General to Europa, Enceladus, Titan and other Ocean Worlds - Technologies and components relevant to life detection instruments (e.g., microfluidic analyzer, microelectromechanical systems (MEMS) chromatography/mass spectrometers, laser-ablation mass spectrometer, fluorescence microscopic imager, Raman spectrometer, tunable laser system, liquid chromatography/mass spectrometer, X-ray fluorescence, digital holographic microscope-fluorescence microscope, antibody microarray biosensor, nanocantilever biodetector, etc.) Technologies for high radiation environments, e.g., radiation mitigation strategies, radiation tolerant detectors, and readout electronic components, which enable orbiting instruments to be both radiation-hard and undergo the planetary protection requirements of sterilization (or equivalent).
  • Collecting samples for a variety of science purposes is also sought. These include samples that allow for determination of the chemical and physical properties of the source ocean, samples for detailed characterization of the organics present in the gas and particle phases, and samples for analysis for biomarkers indicative of life. Front-end system technologies include sample collection systems and subsystems capable of capture, containment, and/or transfer of gas, liquid, ice, and/or mineral phases from plumes to sample processing and/or instrument interfaces.
  • Technologies for characterization of collected sample parameters including mass, volume, total dissolved solids in liquid samples, and insoluble solids. Sample collection and sample capture for in-situ imaging. Systems capable of high-velocity sample collection with minimal sample alteration to allow for habitability and life detection analyses. Microfluidic sample collection systems that enable sample concentration and other manipulations. Plume material collection technologies that minimize risk of terrestrial contamination, including organic chemical and microbial contaminates. These technologies would enable high-priority sampling and potential sample return from the plumes of Enceladus with a fly-by mission. This would be a substantial cost savings over a landed mission.
  • Europa - Life detection approaches optimized for evaluating and analyzing the composition of ice matrices with unknown pH and salt content. Instruments capable of detecting and identifying organic molecules (in particular biomolecules), salts and/or minerals important to understanding the present conditions of Europa's ocean are sought (such as high resolution gas chromatograph or laser desorption mass spectrometers, dust detectors, organic analysis instruments with chiral discrimination, etc.). These developments should be geared towards analyzing and handling very small sample sizes (microg to mg) and/or low column densities/abundances. Also of interest are imagers and spectrometers that provide high performance in low-light environments (visible and NIR imaging spectrometers, thermal imagers, etc.), as well as instruments capable of improving our understanding of Europa's habitability by characterizing the ice, ocean, and deeper interior and monitoring ongoing geological activity such as plumes, ice fractures, and fluid motion (e.g., seismometers, magnetometers). Improvements to instruments capable of gravity (or other) measurements that might constrain properties such as ocean and ice shell thickness will also be considered.
  • Enceladus (including plume material and E-ring particles) - Life detection approaches optimized for analyzing plume particles, as well as for determining the chemical state of Enceladus icy surface materials (particularly near plume sites). Instruments capable of detecting and identifying organic molecules (in particular biomolecules), salts and/or minerals important to understand the present conditions of the Enceladus ocean are sought (such as high resolution gas chromatograph or laser desorption mass spectrometers, dust detectors, organic analysis instruments with chiral discrimination, etc.). These developments should be geared towards analyzing and handling very small sample sizes (microg to mg) and/or low column densities/abundances. Also of interest are imagers and spectrometers that provide high performance in low-light environments (visible and NIR imaging spectrometers, thermal imagers, etc.), as well as instruments capable of monitoring the bulk chemical composition and physical characteristics of the plume (density, velocity, variation with time, etc.). Improvements to instruments capable of gravity (or other) measurements that might constrain properties such as ocean and ice shell thickness will also be considered.
  • Titan - Life detection approaches optimized for searching for biosignatures and biologically relevant compounds in Titan's lakes, including the presence of diagnostic trace organic species, and also for analyzing Titan's complex aerosols and surface materials. Mechanical and electrical components and subsystems that work in cryogenic (95 K) environments; sample extraction from liquid methane/ethane, sampling from organic 'dunes' at 95 K and robust sample preparation and handling mechanisms that feed into mass analyzers are sought. Balloon instruments, such as IR spectrometers, imagers, meteorological instruments, radar sounders, solid, liquid, air sampling mechanisms for mass analyzers, and aerosol detectors are also solicited. Low mass and power sensors, mechanisms and concepts for converting terrestrial instruments such as turbidimeters and echo sounders for lake measurements, weather stations, surface (lake and solid) properties packages, etc. to cryogenic environments (95 K).
  • Other Ocean Worlds targets may include Ganymede, Callisto, Ceres, etc.

Proposers are strongly encouraged to relate their proposed development to:

• NASA's future Ocean Worlds exploration goals (see references)
• Existing flight instrument capability, to provide a comparison metric for assessing proposed improvements.

Proposed instrument architectures should be as simple, reliable, and low risk as possible while enabling compelling science. Novel instrument concepts are encouraged particularly if they enable a new class of scientific discovery. Technology developments relevant to multiple environments and platforms are also desired.

Proposers should show an understanding of relevant space science needs, and present a feasible plan to fully develop a technology and infuse it into a NASA program.

References

For the NASA Roadmap for Ocean World Exploration see: http://www.lpi.usra.edu/opag/ROW [228]

In situ instruments and technologies for NASA's Ocean Worlds exploration goals see: https://www.nasa.gov/specials/ocean-worlds/ [70]

NASA technology solicitation, see ROSES 2016/C.20 Concepts for Ocean worlds Life Detection Technology (COLDTECH) call:
https://nspires.nasaprs.com/external/solicitations/summary.do?method=init&solId={5C43865B-0C93-6ECA-BCD2-A3783CB1AAC8}&path=init [229]

Instrument Concepts for Europa Exploration 2 (final text released May 17, 2018;.PDF): https://nspires.nasaprs.com/external/viewrepositorydocument/cmdocumentid=628697/solicitationId=%7B17B73E96-6B65-FE78-5B63-84C804831035%7D/viewSolicitationDocument=1/C.23%20ICEE2%20Schulte%20POC.pdf [230]

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software

Desired Deliverables Description

In-situ instruments in TRL 3 - 5 for Ocean Worlds exploration

State of the Art and Critical Gaps

In situ instruments and technologies are essential bases to achieve NASA's Ocean Worlds exploration goals. There are currently some in situ instruments for diverse Ocean Worlds bodies. However, there are ever increasing science and exploration requirements and challenges for diverse Ocean Worlds bodies. For example, there are urgent needs for the exploration of icy or liquid surface on Europa, Enceladus, Titan, Ganymede, Callisto, etc. and, plumes from planetary bodies such as Enceladus.

To narrow the critical gaps between the current state of art and the technology needed for the ever increasing science/exploration requirements, in-situ technologies are being sought to achieve much higher resolution and sensitivity with significant improvements over existing capabilities, and at the same time with lower resource (mass, power and volume) requirements.

Relevance / Science Traceability

In situ instruments and technologies are essential bases to achieve Science Mission Directorate's (SMD) planetary science goals summarized in Decadal Study (National Research Council’s Vision and Voyages for Planetary Science in the Decade 2013-2022.) In situ instruments and technologies play indispensable role for NASA’s New Frontiers and Discovery missions to various planetary bodies.

NASA SMD has two programs to bring this subtopic technologies to higher level: PICASSO and MatISSE. The Planetary Instrument Concepts for the Advancement of Solar System Observations (PICASSO) Program invests in low-TRL technologies and funds instrument feasibility studies, concept formation, proof-of-concept instruments, and advanced component technology. The Maturation of Instruments for Solar System Exploration (MatISSE) Program invests in mid-TRL technologies and enables timely and efficient infusion of technology into planetary science missions. The PICASSO and MatISSE are in addition to Phase III opportunities.

Scope Description

The 2013 National Research Council’s, Solar and Space Physics: A Science for a Technological Society (http://nap.edu/13060 [204]) motivates this subtopic: “Deliberate investment in new instrument concepts is necessary to acquire the data needed to further solar and space physics science goals, reduce mission risk, and maintain an active and innovative hardware development community.” This subtopic solicits development of advanced remote sensing instrument technologies and components suitable for deployment on heliophysics missions. These technologies must be capable of withstanding operation in space environments, including the expected pressures, radiation levels, launch and impact stresses, and range of survival and operational temperatures. Technologies that reduce mass, power, volume, and data rates for instruments and instrument components without loss of scientific capability are of particular importance. In addition, technologies that can increase instrument resolution and sensitivity or achieve new and innovative scientific measurements are solicited. For example missions, see https://science.nasa.gov/missions-page?field_division_tid=5&field_phase_tid=All [232]. For details of the specific requirements see the Heliophysics Decadal Survey. Technologies that support science aspects of missions in NASA’s Living With a Star and Solar-Terrestrial Probe programs are of top priority, including long-term missions like Interstellar Probe mission (as called out in the Decadal Survey).

Remote sensing technologies are being sought to achieve much higher resolution and sensitivity with significant improvements over existing capabilities. Remote sensing technologies amenable to CubeSats and SmallSats are also encouraged. Specifically, this subtopic solicits instrument development that provides significant advances in the following areas:

• Light Detection and Ranging (LIDAR) systems for high-power, high frequency geospace remote sensing, such as sodium and helium lasers
• Technologies or components enabling auroral, airglow, geospace, and solar imaging in the visible, far-ultraviolet and soft x-ray (e.g., mirrors and gratings with high-reflectance coatings, multi-layer coatings, narrow-band filters, and blazed gratings with high ruling densities)
• Technologies that enable the development of dedicated solar flare sensors with intrinsic ion suppression and sufficient angular resolution in the extreme UV (EUV) to soft x-ray wavelength range such as fast cadence charge-coupled devices, complementary metal-oxide semiconductor devices
• Technologies that enable x-ray detectors to observe bright solar flares in x-ray from 1 to hundreds of keV without saturation
• Technologies that attenuate solar x-ray fluences by flattening the observed spectrum by a factor of 100 to 1000 across the energy range encompassing both low and high energy x-rays – preferably flight programmable
• X-ray optics technologies to reduce the size, complexity, or mass or to improve the point spread function of solar telescopes used for imaging solar x-rays in the ~1 to 300 keV range
• Technologies that allow polarization and wavelength filtering without mechanical moving parts

Proposers are strongly encouraged to relate their proposed development to NASA's future heliophysics goals as set out in the Heliophysics Decadal Survey (2013-2022) and the NASA Heliophysics Roadmap (2014-2033). Proposed instrument components and/or architectures should be as simple, reliable, and low risk as possible while enabling compelling science. Novel instrument concepts are encouraged particularly if they enable a new class of scientific discovery. Technology developments relevant to multiple environments and platforms are also desired. Proposers should show an understanding of relevant space science needs, and present a feasible plan to fully develop a technology and infuse it into a NASA program. Detector technology proposals should be referred to the S116 subtopic.

References

For example missions, see https://science.nasa.gov/missions [233]

For details of the specific requirements see the National Research Council’s, Solar and Space Physics: A Science for a Technological Society (http://nap.edu/13060 [204]).

For details of NASA's Heliophysics roadmap, see the NASA Heliophysics Roadmap:  https://smd-prod.s3.amazonaws.com/science-red/s3fs-public/atoms/files/2014_HelioRoadmap_Final_Reduced_0.pdf [196]

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software

Desired Deliverables Description

Remote sensing instruments in TRL 3 - 5 for heliophysics science purpose

State of the Art and Critical Gaps

Remote sensing instruments and technologies are essential bases to achieve Science Mission Directorate's (SMD) Heliophysics goals summarized in National Research Council’s, Solar and Space Physics: A Science for a Technological Society. These instruments and technologies play indispensable roles for NASA’s LWS and STP mission programs, as well as a host of smaller spacecraft in the Explorers Program.  In addition, there is growing demand for remote sensing technologies amenable to CubeSats and SmallSats. To narrow the critical gaps between the current state of art and the technology needed for the ever increasing science/exploration requirements, remote sensing technologies are being sought to achieve much higher resolution and sensitivity with significant improvements over existing capabilities, and at the same time with lower mass, power and volume.

Relevance / Science Traceability

Remote sensing instruments and technologies are essential bases to achieve SMD's Heliophysics goals summarized in National Research Council’s, Solar and Space Physics: A Science for a Technological Society. These instruments and technologies play indispensable roles for NASA’s Living with a Star (LWS) and Solar Terrestrial Probe (STP) mission programs, as well as a host of smaller spacecraft in the Explorers Program. In addition, there is growing demand for remote sensing technologies amenable to Cubesats and Smallsats. NASA SMD has two excellent programs to bring this subtopic technologies to higher level: Heliophysics Instrument Development for Science (H-TIDeS) and Heliophysics Flight Opportunities for Research and Technology (H-FORT). H-TIDeS seeks to advance the development of technologies and their application to enable investigation of key heliophysics science questions. This is done through incubating innovative concepts and development of prototype technologies. It is intended that technologies developed through H-TIDeS would then be proposed to H-FORT to mature by demonstration in a relevant environment. The H-TIDeS and H-FORT programs are in addition to Phase III opportunities.

Scope Title
Research and Development Opportunities for Metamaterials

Scope Description

Metamaterials are man-made (synthesized) composite materials whose electromagnetic, acoustic, optical, etc. properties are determined by their constitutive structural materials and their configurations. Metamaterials can be precisely tailored to manipulate electromagnetic waves, including visible light, microwaves, and other parts of the spectrum, in ways that no natural materials can. The development of metamaterials continues to redefine the boundaries of materials science. In the field of electromagnetic research and beyond, these materials offer excellent design flexibility with their customized properties and their tunability under external stimuli.  These properties enable Metamaterials to be a game changer for many technologies needing reduced size, weight, and power (SWaP), enhanced tunability and reconfigurability. Topics of interest for NASA's applications are listed below.  

1. Beam shaping with metamaterials (at optical as well as microwave wavelengths).
2. Control of emission and absorption with metamaterials (for applications such as tunable lenses).
3. Engineering mid-infrared and optical nonlinearities with metamaterials.
4. Development of microwave and millimeter-wave metamaterials: radar scanning systems, flat panel antennas, mobile communication antennas, novel magnetic materials and high-performance absorbing and shielding materials for electromagnetic compatibility (EMC) and reduction of radio frequency interference (RFI).
5. Thin-film technology incorporated with metamaterial nanocomposites to collect light from wide angles and absorption over wide spectrum.
6. Tunable, reconfigurable metamaterials using liquid crystal medium (Applications: IR and Optical spectrometers).
7. Development of artificial ferrites and artificial dielectrics using metamaterial concepts to design electrically small, lightweight, and efficient RF components.
8. Transformation electromagnetic techniques with advances in fabricating metamaterials (Applications: microwaves and infrared wavelength sensors).

Expected TRL or TRL range at completion of the project: 1 to 3

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Research

Desired Deliverables Description

It is expected at the end of year one for selected teams to provide a comprehensive feasibility study to address an applicable area of interest within the field of metamaterial technology. Deliverables in subsequent years could involve prototypes and demonstration of performance.

State of the Art and Critical Gaps

Metamaterial research is interdisciplinary and involves such fields as electrical engineering, electromagnetics, classical optics, solid state physics, microwave and antenna engineering, optoelectronics, material sciences, as well as nanoscience and semiconductor engineering.
Potential applications of metamaterials are diverse and include: optical filters, remote aerospace applications, sensor detection, radomes, and lenses for high-gain antennas. Metamaterials also offer the potential to create superlenses, which could allow imaging below the diffraction limit that is the minimum resolution that can be achieved by conventional glass lenses. Transformation optics is a technique that simplifies the modeling of optical devices by altering the coordinate system to control the trajectories of light rays. At microwave frequencies, the first, imperfect invisibility cloak was realized in 2006.

Relevance / Science Traceability

Metamaterial technology has the biggest potential to impact the future of space borne instrumentation by reducing size, weight, and power (SWaP) as well as the overall cost of future space missions. There is especially a need for these improved capabilities in the development of instruments for Planetary and the Earth Science missions to reduce their cost.  Due to the nature of metamaterials, there are a multitude of possible applications for this technology. For example, applications of metamaterials for remote sensing include tunability, complex filtering, light channeling/trapping, superbeaming, and determination of optical angular momentum modes via metamaterials. For additional information regarding Science Mission Directorate (SMD) technology needs, please review https://science.nasa.gov/about-us/science-strategy/decadal-surveys [28].

References

www.centerformetamaterials.org/ [235]

Alici, Kamil Boratay; Özbay, Ekmel (2007). "Radiation properties of a split ring resonator and monopole composite". Physica status solidi (b). 244 (4): 1192–96. Bibcode:2007PSSBR.244.1192A. doi:10.1002/pssb.200674505.

Brun, M.; S. Guenneau; and A.B. Movchan (2009-02-09). "Achieving control of in-plane elastic waves". Appl. Phys. Lett. 94 (61903): 1–7. arXiv:0812.0912 Freely accessible. Bibcode: 2009ApPhL..94f1903B. doi:10.1063/1.3068491.

Caloz, C.; Chang, C.-C.; Itoh, T. (2001). "Full-wave verification of the fundamental properties of left-handed materials in waveguide configurations" (PDF). J. Appl. Phys. 90 (11): 11. Bibcode:2001JAP.90.5483C. doi:10.1063/1.1408261.

Caloz, C.; Itoh, T. (2002). "Application of the Transmission Line Theory of Left-handed (LH) Materials to the Realization of a Microstrip 'LH line'". IEEE Antennas and Propagation Society International Symposium. 2: 412. doi:10.1109/APS.2002.1016111. ISBN 0-7803-7330-8.

Cotton, Micheal G. (December 2003). "Applied Electromagnetics" (PDF). 2003 Technical Progress Report (NITA – ITS). Boulder, CO: NITA – Institute for Telecommunication Sciences. Telecommunications Theory (3): 4–5. Retrieved 2009-09-14.

Eleftheriades, G.V.; Iyer A.K. & Kremer, P.C. (2002). "Planar Negative Refractive Index Media Using Periodically L-C Loaded Transmission Lines". IEEE Transactions on Microwave Theory and Techniques. 50 (12): 2702–12. Bibcode:2002ITMTT..50.2702E. doi:10.1109/TMTT.2002.805197.

Guenneau, S. B.; Movchan, A.; Pétursson, G.; Anantha Ramakrishna, S. (2007). "Acoustic metamaterials for sound focusing and confinement". New Journal of Physics. 9 (11): 399. Bibcode:2007NJPh....9..399G. doi:10.1088/1367-2630/9/11/399.

Kock, W. E. (1946). "Metal-Lens Antennas". IRE Proc. 34 (11): 828–36. doi:10.1109/JRPROC.1946.232264.

Kock, W.E. (1948). "Metallic Delay Lenses". Bell. Sys. Tech. Jour. 27: 58–82. doi:10.1002/j.1538-7305.1948.tb01331.x.

Rainsford, Tamath J.; D. Abbott; Abbott, Derek (9 March 2005). Al-Sarawi, Said F, ed. "T-ray sensing applications: review of global developments". Proc. SPIE. Smart Structures, Devices, and Systems II. Conference Location: Sydney, Australia 2004-12-13: The International Society for Optical Engineering. 5649 Smart Structures, Devices, and Systems II (Poster session): 826–38. Bibcode:2005SPIE.5649..826R. doi:10.1117/12.607746.

Zouhdi, Saïd; Ari Sihvola; Alexey P. Vinogradov (December 2008). Metamaterials and Plasmonics: Fundamentals, Modelling, Applications. New York: Springer-Verlag. pp. 3–10, Chap. 3, 106. ISBN 978-1-4020-9406-4.

Werner, Douglas H. (editor) and Do-Hoon Kwon (editor) 2014. Transformation Electromagnetics and Metamaterials: Fundamental Principles and Applications.

Scope Title
Quantum Sensing and Measurement

Scope Description

This Quantum Sensing subtopic calls for proposals using quantum systems to achieve unprecedented measurement sensitivity and performance, including quantum-enhanced methodologies that outperform their classical counterparts. Shepherded by advancements in our ability to detect and manipulate single quantum objects, the so called "Second Quantum Revolution" is upon us.  The emerging quantum sensing technologies promise unrivaled sensitivities and are potentially game changing in precision measurement fields.  Significant gains include technology important for a range of NASA missions such as:  efficient photon detection, optical clocks, gravitational wave sensing, ranging, and interferometry.  Atom Interferometry and Quantum Communication focused proposals should apply to those specific subtopics and are not covered in this Quantum Sensing and Measurement subtopic.

Specifically identified applications of interested include quantum sensing methodologies achieving the optimal collection light for photon-starved astronomical observations, quantum-enhanced ground penetrating radar, and quantum-enhanced telescope interferometry.

• Superconducting Quantum Interference Device (SQUIDs) systems for enhanced multiplexing factor reading out of arrays of cryogenic energy-resolving single-photon detectors, including the supporting resonator circuits, amplifiers, and room temperature readout electronics.
• Quantum light sources capable of efficiently and reliably producing prescribed quantum states including entangled photons, squeezed states, photon number states, and broadband correlated light pulses. Such entangled sources are sought for the vis-IR and in the microwave entangled photons sources for quantum ranging and ground penetrating radar.
• On-demand single photon sources with narrow spectral linewidth are needed for system calibration of single photon counting detectors and energy-resolving single-photon detector arrays in the MIR, NIR, and visible.  Such sources are sought for operation at cryogenic temperatures for calibration on the ground and aboard space instruments.

References

• 2019 NASA Fundamental Physics and Quantum Technology Workshop. Washington DC April 8-10, 2019.
• Quantum Communication, Sensing and Measurement in Space, Team Leads: Erkmen, Shapiro, and Schwab 2012
  • http://kiss.caltech.edu/final_reports/Quantum_final_report.pdf [237]
• National Quantum Initiative Act:
  • https://www.congress.gov/congressional-report/115th-congress/house-report/950/1 [238]
  • https://www.congress.gov/congressional-report/115th-congress/senate-report/389 [239]
  • https://www.lightourfuture.org/getattachment/7ad9e04f-4d21-4d98-bd28-e1239977e262/NPI-Recommendations-to-HSC-for-National-Quantum-Initiative-062217.pdf [240]
• European Union Quantum Flagship Program: https://qt.eu [241]
• UK National Quantum Technologies Programme http://uknqt.epsrc.ac.uk [242]
• DLR Institute of Quantum Technologies https://www.dlr.de/qt/en/desktopdefault.aspx/tabid-13498/23503_read-54020/ [243]
• C. L. Degen, F. Reinhard, and P. Cappellaro, Quantum Sensing, Rev. Mod. Phys. 89, 035002 (2017).

Expected TRL or TRL range at completion of the project: 2 to 4

Desired Deliverables of Phase II

Prototype, Analysis, Research

Desired Deliverables Description

NASA is seeking innovative ideas and creative concepts for science sensor technologies using quantum sensing techniques.  The proposals should include results from designs and models, proof-of-concept demonstrations and prototypes showing the performance of the novel quantum sensor.

State of the Art and Critical Gaps

Sources for entangled photons.

Quantum dot source produced entangled photons with a fidelity of 0.90, a pair generation rate of 0.59, a pair extraction efficiency of 0.62, and a photon indistinguishability of 0.90 simultaneously. (881 nm light) at 10 MHz.  Wang Phys. Rev. Lett. 122, 113602 2019.

Spectral brightness of 0.41 MHz/mW/nm for multi-mode and 0.025 MHz/mW/nm for single mode coupling. Jabir Scientific Reports volume 7, Article number: 12613 (2017).

Higher brightness and multiple entanglement and heralded multiphoton entanglement and boson sampling sources. Sources that produce photon number states or Fock states are also sought for various applications including energy-resolving single photon detector applications.

For energy resolving single photon detectors current state of the art multiplexing can achieve kilopixel detector arrays which with advances in microwave SQUID mux can be increased to megapixel arrays. (Morgan Physics Today 71, 8, 28 (2018)).

Relevance / Science Traceability

Quantum technologies enable a new generation in sensitivities and performance.  Including atomic clocks and ultra-precise sensors with applications ranging from natural resource exploration and biomedical diagnostic to navigation.

HEOMD - Astronaut Health Monitoring.

SMD - Earth, Planetary and Astrophysics including imaging spectrometers on a chip across the electromagnetic spectrum from X-ray through the IR.

STMD - Game changing technology for small spacecraft communication and navigation (optical communication, laser ranging, gyroscopes).

STTR- Rapid increased interest.

Space Technology Roadmap - 6.2.2, 13.1.3, 13.3.7, all sensors 6.4.1, 7.1.3, 10.4.1, 13.1.3, 13.4.3, and 14.3.3.

Scope Title
Control of Scattered Starlight with Coronagraphs and Starshades

Scope Description

This subtopic addresses the unique problem of imaging and spectroscopic characterization of faint astrophysical objects that are located within the obscuring glare of much brighter stellar sources. Examples include planetary systems beyond our own, the detailed inner structure of galaxies with very bright nuclei, binary star formation, and stellar evolution. Contrast ratios of one million to ten billion over an angular spatial scale of 0.05 - 1.5 arcsec are typical of these objects. Achieving a very low background requires control of both scattered and diffracted light. The failure to control either amplitude or phase fluctuations in the optical train severely reduces the effectiveness of starlight cancellation schemes.

This innovative research focuses on advances in coronagraphic instruments, starlight cancellation instruments, and potential occulting technologies that operate at visible and near infrared wavelengths. The ultimate application of these instruments is to operate in space as part of a future observatory mission concepts such as the Habitable Exoplanet Observatory (HabEx) and Large Ultraviolet Optical Infrared Surveyor (LUVOIR). Measurement techniques include imaging, photometry, spectroscopy, and polarimetry. There is interest in component development and innovative instrument design, as well as in the fabrication of subsystem devices to include, but not limited to, the following areas:

Starlight Suppression Technologies:

• Hybrid metal/dielectric and polarization apodization masks for diffraction control of phase and amplitude for coronagraph scaled starshade experiments.
• Low-scatter, low-reflectivity, sharp, flexible edges for control of solar scatter in starshades.
• Low-reflectivity coatings for flexible starshade optical shields.
• Systems to measure spatial optical density, phase inhomogeneity, scattering, spectral dispersion, thermal variations, and to otherwise estimate the accuracy of high-dynamic range apodizing masks.
• Methods to distinguish the coherent and incoherent scatter in a broadband speckle field.

Wavefront Measurement and Control Technologies:

• Small stroke, high precision, deformable mirrors and associated driving electronics scalable to 10,000 or more actuators (both to further the state-of-the-art towards flight-like hardware and to explore novel concepts). Multiple deformable mirror technologies in various phases of development and processes are encouraged to ultimately improve the state-of-the-art in deformable mirror technology. Process improvements are needed to improve repeatability, yield, and performance precision of current devices.
• Multiplexers with ultra-low power dissipation for electrical connection to deformable mirrors
• Low-order wavefront sensors for measuring wavefront instabilities to enable real-time control and post-processing of aberrations.
• Thermally and mechanically insensitive optical benches and systems.

Optical Coating and Measurement Technologies:

• Instruments capable of measuring polarization cross-talk and birefringence to parts per million.
• Polarization-insensitive coatings for large optics.
• Methods to measure the spectral reflectivity and polarization uniformity across large optics.
• Methods to apply carbon nanotube coatings on the surfaces of the coronagraphs for broadband suppression from visible to near infrared (NIR).

References

See SPIE conference papers and articles published in the Journal of Astronomical Telescopes and Instrumentation on high contrast coronagraphy, segmented coronagraph design and analysis, and starshades.

Websites:

• Exoplanet Exploration - Planets Beyond Our Solar System: https://exoplanets.jpl.nasa.gov [245]
• Exoplanet Exploration Program: https://exoplanets.nasa.gov/exep/ [246]
• Goddard Space Flight Center: https://www.nasa.gov/goddard [247]

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Research

Desired Deliverables Description

This subtopic solicits proposals to develop components that improve the footprint, robustness, power consumption, reliability, and wavefront quality of high-contrast, low-temporal bandwidth, adaptive optics systems. These include ASIC drivers that easily integrate with the deformable mirrors, improved connectivity technologies, as well as high-actuator count deformable mirrors  with high-quality, ultrastable wavefronts.

It also seeks coronagraph masks that can be tested in ground-based high-contrast testbeds in place at a number of institutions, as well as devices to measure the masks to inform optical models. The masks include transmissive scalar, polarization-dependent, and spatial apodizing masks including those with extremely low reflectivity regions that allow them to be used in reflection.

The subtopic seeks samples of optical coatings that reduce polarization and can be applied to large optics, and methods and instruments to characterize them over large optical surfaces.

Finally, for starshades, the subtopic seeks low reflectivity and potentially diffraction-controlling edges that minimize scattered sunlight while also remaining robust to handling and cleaning.  Low-reflectivity optical coatings that can be applied to the surfaces for the large (hundreds of square meters) optical shield are also desired.

State of the Art and Critical Gaps

Coronagraphs have been demonstrated to achieve high contrast in moderate bandwidth in laboratory environments. Starshades will enable even deeper contrast over broader bands but to date have demonstrated deep contrast in narrow band light. The extent to which the telescope optics will limit coronagraph performance is a function of the quality of the optical coating and the ability to control polarization over the full wavefront. Neither of these technologies is well characterized at levels required for 1e10 contrast. Wavefront control using deformable mirrors is critical. Controllability and stability to picometer levels is required. To date, deformable mirrors have been up to the task of providing contrast approaching 1e10, but they require thousands of wires, and overall wavefront quality and stroke remain concerns.

Relevance / Science Traceability

These technologies are directly applicable to the Wide Field Infrared Survey Telescope (WFIRST), coronagraph instrument (CGI), and the HabEx and LUVOIR concept studies.

Scope Title

Precision Deployable Optical Structures and Metrology

Scope Description

Future space astronomy missions from ultraviolet to millimeter wavelengths will push the state of the art in current optomechanical technologies. Size, dimensional stability, temperature, risk, manufacturability, and cost are important factors, separately and in combination. The Large Ultraviolet Optical Infrared Surveyor (LUVOIR) calls for deployed apertures as large as 15 m in diameter, the Origins Space Telescope (OST) for operational temperatures as low as 4 K, LUVOIR and the Habitable Exoplanet Observatory (HabEx) for exquisite optical quality. Methods to construct large telescopes in space are also under development.  Additionally, sunshields for thermal control and starshades for exoplanet imaging require deployment schemes to achieve 30-70 m class space structures.

This subtopic addresses the need to mature technologies that can be used to fabricate 10-20 m class, lightweight, ambient or cryogenic flight qualified observatory systems and subsystems (telescopes, sunshields, starshades). Proposals to fabricate demonstration components and subsystems with direct scalability to flight systems through validated models will be given preference. The target launch volume and expected disturbances, along with the estimate of system performance, should be included in the discussion. Novel metrology solutions to establish and maintain optical alignment will also be accepted.

Technologies including, but not limited to, the following areas are of particular interest:

Precision structures/materials:

• Low Coefficient Thermal Expansion (CTE)/Coefficient of Moisture Expansion (CME) materials/structures to enable highly dimensionally stable optics, optical benches, metering structures
• Materials/structures to enable deep cryogenic (down to 4 K) operation
• Novel athermalization methods to join materials/structures with differing mechanical/thermal properties
• Lightweight materials/structures to enable high mass-efficiency structures
• Precision joints/latches to enable sub-micron level repeatability
• Mechanical connections providing micro-dynamic stability suitable for robotic assembly

Deployable Technologies:

• Precision deployable modules for assembly of optical telescopes (e.g., innovative active or passive deployable primary or secondary support structures)
• Hybrid deployable/assembled architectures, packaging, and deployment designs for large sunshields and external occulters (20-50 m class)
• Packaging techniques to enable more efficient deployable structures

Metrology:

• Techniques to verify dimensional stability requirements at sub-nanometer level precisions (10 – 100 picometers)
• Techniques to monitor and maintain telescope optical alignment for on-ground and in-orbit operation

A successful proposal shows a path toward a Phase II delivery of demonstration hardware scalable to 5-meter diameter for ground test characterization. Proposals should show an understanding of one or more relevant science needs, and present a feasible plan to fully develop the relevant subsystem technologies and to transition into future NASA program(s).

References

Large UV/Optical/IR Surveyor (LUVOIR): https://asd.gsfc.nasa.gov/luvoir/ [198]

Habitable Exoplanet Observatory (HabEx): https://www.jpl.nasa.gov/habex/ [199]

Origins Space Telescope: https://asd.gsfc.nasa.gov/firs/ [221]

What is an Exoplanet? https://exoplanets.nasa.gov/what-is-an-exoplanet/technology/ [249]

NASA in-Space Assembled Telescope (iSAT) Study: https://exoplanets.nasa.gov/exep/technology/in-space-assembly/iSAT_study/ [250]

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Research

Desired Deliverables Description

A successful deliverable would include a demonstration of the functionality and/or performance of a system/subsystem with model predictions to explain observed behavior as well as make predictions on future designs. This should be demonstrated on units that can be scaled to future flight sizes.

State of the Art and Critical Gaps

The James Webb Space Telescope, currently set to launch in 2021, represents the state of the art in large deployable telescopes. The Wide Field Infrared Survey Telescope’s (WFIRST) coronagraph instrument (CGI) will drive telescope/instrument stability requirements to new levels. The mission concepts in the upcoming Astro2020 decadal survey will push technological requirements even further in the areas of deployment, size, stability, lightweighting, and operational temperature. Each of these mission studies have identified technology gaps related to their respective mission requirements.

Relevance / Science Traceability

These technologies are directly applicable to the WFIRST CGI and the HabEx, LUVOIR, and OST mission concepts.

Scope Title

Optical Components and Systems for Large Telescope Missions

Scope Description

To accomplish NASA’s high-priority science at all levels (flagship, probe, Medium-Class Explorers (MIDEX), Small Explorers (SMEX), rocket and balloon) requires low-cost, ultra-stable, normal incidence mirror systems with low mass-to-collecting area ratios. Where a mirror system is defined as the mirror substrate, supporting structure, and associated actuation and thermal management systems. After performance, the most important metric for an advanced optical system is affordability or areal cost (cost per square meter of collecting aperture). Current normal incidence space mirrors cost $4 million to $6 million per square meter of optical surface area. This research effort seeks to improve the performance of advanced precision optical components while reducing their cost by 5 to 50 times, to between $100K/m2 to $1M/m2.

Specific metrics are defined for each wavelength application region:

Aperture Diameter for all wavelengths, except Far-IR

• Monolithic: 1 to 8 meters
• Segmented: 3 to 20 meters

For UV/Optical

• Areal Cost < $500K/m2
• Wavefront Figure < 5 nm RMS (via passive design or active deformation control)
• Wavefront Stability < 10 pm/10 min
• First Mode Frequency 60 to 500 Hz
• Actuator Resolution < 1 nm RMS
• Optical Path-length Stability < 1 pm/10,000 seconds for precision metrology
• Areal density < 15 kg/m2 (< 35 kg/m2 with backplane)
• Operating Temperature Range of 250 to 300K

For Far-IR

• Aperture diameter 1 to 4 m (monolithic), or 5 to 10 m (segmented)
• Telescope diffraction-limited at <30 microns at operating temperature 4 K
• Cryo-Deformation < 100 nm RMS
• Areal cost < $500K/m2
• Production rate > 2 m2 per month
• Areal density < 15 kg/m2 (< 40 kg/m2 with backplane)
• Thermal conductivity at 4 K > 2 W/m*K
• Survivability at temperatures ranging from 315 K to 4 K

For EUV

• Surface Slope < 0.1 micro-radian

Also needed is ability to fully characterize surface errors and predict optical performance.

Proposals must show an understanding of one or more relevant science needs, and present a feasible plan to develop the proposed technology for infusion into a NASA program: sub-orbital rocket or balloon; competed SMEX or MIDEX; or, Decadal class mission. Successful proposals will demonstrate an ability to manufacture, test and control ultra-low-cost optical systems that can meet science performance requirements and mission requirements (including processing and infrastructure issues). Material behavior, process control, active and/or passive optical performance, and mounting/deploying issues should be resolved and demonstrated.

References

The Habitable Exoplanet Imager (HabEx) and Large UVOIR (LUVOIR) space telescope studies are developing concepts for UVOIR space telescopes for exoEarth discovery and characterization, exoplanet science, general astrophysics and solar system astronomy. The HabEx Interim Report is available at: https://www.jpl.nasa.gov/habex/documents/ [252]. \ The LUVOIR Interim Report is available at: https://asd.gsfc.nasa.gov/luvoir/ [198].

The Origins Space Telescope (OST) is a single-aperture telescope concept for the Far-Infrared Surveyor mission described in the NASA Astrophysics Roadmap, "Enduring Quests, Daring Visions: NASA Astrophysics in the Next Three Decades": https://smd-prod.s3.amazonaws.com/science-pink/s3fs-public/atoms/files/secure-Astrophysics_Roadmap_2013_0.pdf [253].

The OST mission is described on the website: https://origins.ipac.caltech.edu [254].

The Space Infrared Interferometric Telescope (SPIRIT) and its optical system requirements are described on the website: https://asd.gsfc.nasa.gov/cosmology/spirit/ [255].

LISA (Laser Interferometer Space Antenna) mission description: https://lisa.nasa.gov/ [256].

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Hardware, Research

Desired Deliverables Description

An ideal Phase 1 deliverable would be a precision optical system of at least 0.25 meters; or a relevant sub-component of a system; or a prototype demonstration of a fabrication, test or control technology leading to a successful Phase 2 delivery; or a reviewed preliminary design and manufacturing plan which demonstrates feasibility. While detailed analysis will be conducted in Phase 2, the preliminary design should address how optical, mechanical (static and dynamic) and thermal designs and performance analysis will be done to show compliance with all requirements. Past experience or technology demonstrations which support the design and manufacturing plans will be given appropriate weight in the evaluation.

An ideal Phase 2 project would further advance the technology to produce a flight-qualifiable optical system greater than 0.5 meters or relevant sub-component (with a TRL in the 4 to 5 range); or a working fabrication, test or control system. Phase 1 and Phase 2 mirror system or component deliverables would be accompanied by all necessary documentation, including the optical performance assessment and all data on processing and properties of its substrate materials. A successful mission oriented Phase 2 would have a credible plan to deliver for the allocated budget a fully assembled and tested telescope assembly which can be integrated into the potential mission; and, demonstrate an understanding of how the engineering specifications of their system meets the performance requirements and operational constraints of the mission (including mechanical and thermal stability analysis).

State of the Art and Critical Gaps

Current normal incidence space mirrors cost $4 million to $6 million per square meter of optical surface area. This research effort seeks a cost reduction for precision optical components by 5 to 50 times, to between $100K/m2 to $1M/m2.

Relevance / Science Traceability

S2.03 primary supports potential Astrophysics Division missions. S2.03 has made optical systems in the past for potential balloon experiments. Future potential Decadal missions include LISA, Habitable Exoplanet Observatory (HabEx), Large UV/Optical/Near-IR Surveyor (LUVOIR) and the Origins Space Telescope (OST).

Scope Title
Balloon Planetary Telescope

Scope Description

Astronomy from a stratospheric balloon platform offers numerous advantages for planetary science. At typical balloon cruise altitudes (100,000 to 130,000 ft.), 99%+ of the atmospheric is below the balloon and the attenuation due to the remaining atmosphere is small, especially in the near ultraviolet band and in the infrared bands near 2.7 and 4.25 µm. The lack of atmosphere nearly eliminates scintillation and allows the resolution potential of relatively large optics to be realized, and the small amount of atmosphere reduces scattered light and allows observations of brighter objects even during daylight hours.

For additional discussion of the advantages of observations from stratosphere platforms, refer to “Planetary Balloon-Based Science Platform Evaluation and Program Implementation - Final Report,” Dankanich et.al. (Available from https://ntrs.nasa.gov/ [257], search for "NASA/TM-2016-218870")

To perform Planetary Science requires a 1-meter class telescope 500 nm diffraction limited performance or Primary Mirror System that can maintain < 10 nm rms surface figure error for elevation angles ranging from 0 to 60 degrees over a temperature range from 220K to 280K.

Phase I will produce a preliminary design and report including initial design requirements such as wave-front error budget, mass allocation budget, structural stiffness requirements, etc., trade studies performed and analysis that compares the design to the expected performance over the specified operating range. Development challenges shall be identified during phase I including trade studies and challenges to be addressed during Phase II with subsystem proof of concept demonstration hardware. If Phase II can only produce a sub-scale component, then it should also produce a detailed final design, including final requirements (wave-front error budget, mass allocation, etc) and performance assessment over the specified operating range.

Additional information about Scientific Balloons can be found at https://www.csbf.nasa.gov/docs.html [258].

Telescope Specifications:

• Diameter > 1 meter
• System Focal Length 14 meter (nominal)
• Diffraction Limit < 500 nm
• Mass < 300 kg
• Shock 10G without damage
• Elevation 0 to 60 degrees
• Temperature 220 to 280 K

Primary Mirror Assembly Specifications:

• Diameter > 1 meter
• Radius of Curvature 3 meters (nominal)
• Surface Figure Error < 10 nm rms
• Mass < 150 kg
• Shock 10G without damage
• Elevation 0 to 60 degrees
• Temperature 220 to 280 K

References

For additional discussion of the advantages of observations from stratosphere platforms, refer to “Planetary Balloon-Based Science Platform Evaluation and Program Implementation - Final Report,” Dankanich et.al. (Available from https://ntrs.nasa.gov/ [257], search for "NASA/TM-2016-218870")

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware

Desired Deliverables Description

If Phase II can only produce a sub-scale component, then it should also produce a detailed final design, including final requirements (wave-front error budget, mass allocation, etc.) and performance assessment over the specified operating range.

State of the Art and Critical Gaps

To perform Planetary Science requires a 1-meter class telescope 500 nm diffraction limited performance or Primary Mirror System that can maintain < 10 nm rms surface figure error for elevation angles ranging from 0 to 60 degrees over a temperature range from 220K to 280K.
Significant science returns may be realized through observations in the 300 nm to 5 μm range.
Current SOA (State of the Art) mirrors made from Zerodur or ULE for example require light weighting to meet balloon mass limitations, and cannot meet diffraction limited performance over the wide temperature range due to the coefficient of thermal expansion limitations.

Relevance / Science Traceability

From “Vision and Voyages for Planetary Science in the Decade 2013-2022”:

• Page 22, Last Paragraph of NASA Telescope Facilities within the Summary Section:
  Balloon- and rocket-borne telescopes offer a cost-effective means of studying planetary bodies at wavelengths inaccessible from the ground.6 Because of their modest costs and development times, they also provide training opportunities for would-be developers of future spacecraft instruments. Although NASA’s Science Mission Directorate regularly flies balloon missions into the stratosphere, there are few funding opportunities to take advantage of this resource for planetary science, because typical planetary grants are too small to support these missions. A funding line to promote further use of these suborbital observing platforms for planetary observations would complement and reduce the load on the already oversubscribed planetary astronomy program.
• Page 203, 5th paragraph, Section titled Earth and Space-Based Telescopes:
  Significant planetary work can be done from balloon-based missions flying higher than 45,000 ft. This altitude provides access to electromagnetic radiation that would otherwise be absorbed by Earth’s atmosphere and permits high-spatial-resolution imaging unaffected by atmospheric turbulence. These facilities offer a combination of cost, flexibility, risk tolerance, and support for innovative solutions that is ideal for the pursuit of certain scientific opportunities, the development of new instrumentation, and infrastructure support. Given the rarity of giant-planet missions, these types of observing platforms (high-altitude telescopes on balloons and sounding rockets) can be used to fill an important data gap.154, 155,156.

Potential Advocates include Planetary Scientists at GSFC, APL, and Southwest Research Institute, etc. The NASA Balloon Workshop.

Potential Projects Gondola for High Altitude Planetary Science (GHAPS).

Scope Title
Large UV/Optical (LUVOIR) and Habitable Exoplanet (HabEx) Missions

Scope Description

Potential UV/Optical missions require 4 to 16 meter monolithic or segmented primary mirrors with < 5 nm RMS surface figures. Active or passive alignment and control is required to achieve system level diffraction limited performance at wavelengths less than 500 nm (< 40 nm RMS wavefront error, WFE). Additionally, potential Exoplanet mission, using an internal coronagraph, requires total telescope wavefront stability on order of 10 pico-meters RMS per 10 minutes. This stability specification places severe constraints on the dynamic mechanical and thermal performance of 4 meter and larger telescope. Potential enabling technologies include: active thermal control systems, ultra-stable mirror support structures, athermal telescope structures, athermal mirror struts, ultra-stable low CTE/high-stability joints, and vibration compensation.

Mirror areal density depends upon available launch vehicle capacities to Sun-Earth L2 (i.e. 15 kg/m2 for a 5 m fairing EELV vs. 150 kg/m2 for a 10 m fairing SLS). Regarding areal cost, a good goal is to keep the total cost of the primary mirror at or below $100M. Thus, an 8-m class mirror (with 50 m2 of collecting area) should have an areal cost of less than $2M/m2. And, a 16-m class mirror (with 200 m2 of collecting area) should have an areal cost of less than $0.5M/m2.

Key technologies to enable such a mirror include new and improved:

• Mirror substrate materials and/or architectural designs
• Processes to rapidly fabricate and test UVO quality mirrors
• Mirror support structures, joints and mechanisms that are athermal or zero CTE at the desired scale
• Mirror support structures, joints and mechanisms that are ultra-stable at the desired scale
• Mirror support structures with low-mass that can survive launch at the desired scale
• Mechanisms and sensors to align segmented mirrors to < 1 nm RMS precisions
• Thermal control (< 1 mK) to reduce wavefront stability to < 10 pm RMS per 10 min
• Dynamic isolation (> 140 dB) to reduce wavefront stability to < 10 pm RMS per 10 min

Also needed is ability to fully characterize surface errors and predict optical performance via integrated opto-mechanical modeling.

Potential solutions for substrate material/architecture include, but are not limited to: ultra-uniform low CTE glasses, silicon carbide, nanolaminates or carbon-fiber reinforced polymer. Potential solutions for mirror support structure material/architecture include, but are not limited to: additive manufacturing, nature inspired architectures, nanoparticle composites, carbon fiber, graphite composite, ceramic or SiC materials, etc. Potential solutions for new fabrication processes include, but are not limited to: additive manufacture, direct precision machining, rapid optical fabrication, roller embossing at optical tolerances, slumping or replication technologies to manufacture 1 to 2 meter (or larger) precision quality components. Potential solutions for achieving the 10 pico-meter wavefront stability include, but are not limited to: metrology, passive, and active control for optical alignment and mirror phasing; active vibration isolation; metrology, passive, and active thermal control.

References

The Habitable Exoplanet Imager (HabEx) and Large UVOIR (LUVOIR) space telescope studies are developing concepts for UVOIR space telescopes for exoEarth discovery and characterization, exoplanet science, general astrophysics and solar system astronomy. The HabEx Interim Report is available at: https://www.jpl.nasa.gov/habex/pdf/interim_report.pdf [259]. The LUVOIR Interim Report is available at: https://asd.gsfc.nasa.gov/luvoir/ [198].

The Origins Space Telescope (OST) is a single-aperture telescope concept for the Far-Infrared Surveyor mission described in the NASA Astrophysics Roadmap, "Enduring Quests, Daring Visions: NASA Astrophysics in the Next Three Decades" (https://smd-prod.s3.amazonaws.com/science-pink/s3fs-public/atoms/files/secure-Astrophysics_Roadmap_2013_0.pdf [253]).

The OST mission is described on the website https://origins.ipac.caltech.edu [254].

The Space Infrared Interferometric Telescope (SPIRIT) and its optical system requirements are described on the website https://asd.gsfc.nasa.gov/cosmology/spirit/ [255].

Expected TRL or TRL range at completion of the project: 2 to 4

Desired Deliverables of Phase II

Analysis, Hardware, Software, Research

Desired Deliverables Description

An ideal Phase 1 deliverable would be a precision optical system of at least 0.25 meters; or a relevant sub-component of a system; or a prototype demonstration of a fabrication, test or control technology leading to a successful Phase 2 delivery; or a reviewed preliminary design and manufacturing plan which demonstrates feasibility. While detailed analysis will be conducted in Phase 2, the preliminary design should address how optical, mechanical (static and dynamic) and thermal designs and performance analysis will be done to show compliance with all requirements. Past experience or technology demonstrations which support the design and manufacturing plans will be given appropriate weight in the evaluation.

An ideal Phase 2 project would further advance the technology to produce a flight-qualifiable optical system greater than 0.5 meters or relevant sub-component (with a TRL in the 4 to 5 range); or a working fabrication, test or control system. Phase 1 and Phase 2 mirror system or component deliverables would be accompanied by all necessary documentation, including the optical performance assessment and all data on processing and properties of its substrate materials. A successful mission oriented Phase 2 would have a credible plan to deliver for the allocated budget a fully assembled and tested telescope assembly which can be integrated into the potential mission; and, demonstrate an understanding of how the engineering specifications of their system meets the performance requirements and operational constraints of the mission (including mechanical and thermal stability analysis).

State of the Art and Critical Gaps

Hubble at 2.4m is the SOA.

Relevance / Science Traceability

S2.03 primary supports potential Astrophysics Division missions. S2.03 has made optical systems in the past for potential balloon experiments. Future potential Decadal missions include LISA, Habitable Exoplanet Observatory (HabEx), Large UV/Optical/Near-IR Surveyor (LUVOIR) and the Origins Space Telescope (OST).

Scope Title
NIR LIDAR Beam Expander Telescope

Scope Description

Potential airborne coherent LIDAR missions need compact 15-cm diameter 20X magnification beam expander telescopes. Potential space based coherent LIDAR missions need at least 50-cm 65X magnification beam expander telescopes. Candidate coherent LIDAR systems (operating with a pulsed 2-micrometer laser) have a narrow, almost diffraction limited field of view, close to 0.8 lambda/D half angle. Aberrations, especially spherical aberration, in the optical telescope can decrease the signal. Additionally, the telescope beam expander should maintain the laser beam’s circular polarization. The incumbent telescope technology is a Dahl-Kirkham beam expander. Technology advance is needed to make the beam expander more compact with less mass while retaining optical performance, and to demonstrate the larger diameter. Additionally, technology for non-moving scanning of the beam expander output is needed.

References

NRC Decadal Surveys at: http://sites.nationalacademies.org/DEPS/ESAS2017/index.htm [260].

https://smd-prod.s3.amazonaws.com/science-pink/s3fs-public/atoms/files/Weather_Focus_Area_Workshop_Report_2015_0.pdf [261].

A. K. DuVivier, J. J. Cassano, S. Greco and G. D. Emmitt, 2017, “A Case Study of Observed and Modeled Barrier Flow in the Denmark Strait in May 2015” Monthly Weather Review 145, 2385 – 2404 (2017): (https://doi.org/10.1175/MWR-D-16-0386.1 [262]). See also Supplemental Material: http://dx.doi.org/10.1175/MWR-D-16-0386.s1 [263]

M. J. Kavaya, J. Y. Beyon, G. J. Koch, M. Petros, P. J. Petzar, U. N. Singh, B. C. Trieu, and J. Yu, “The Doppler Aerosol Wind Lidar (DAWN) Airborne, Wind-Profiling, Coherent-Detection Lidar System: Overview and Preliminary Flight Results,” J. of Atmospheric and Oceanic Technology 34 (4), 826-842 (2014), https://doi.org/10.1175/JTECH-D-12-00274.1 [264]

Scott A. Braun, Ramesh Kakar, Edward Zipser, Gerald Heymsfield, Cerese Albers, Shannon Brown, Stephen L. Durden, Stephen Guimond, Jeffery Halverson, Andrew Heymsfield, Syed Ismail, Bjorn Lambrigtsen, Timothy Miller, Simone Tanelli, Janel Thomas , and Jon Zawislak, “NASA’s Genesis and Rapid Intensification Processes (GRIP) Field Experiment,” Bull. Amer. Meteor. Soc. (BAMS) 94(3), 345-363 (2013), https://doi.org/10.1175/BAMS-D-11-00232.1 [265]

Expected TRL or TRL range at completion of the project: 3 to 4

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Research

Desired Deliverables Description

A detailed design or a small prototype or a full-sized beam expander.

State of the Art and Critical Gaps

The current SOA is a COTS beam expander with a 15-cm diameter primary mirror, a heavy aluminum structure, an Invar rod providing thermally insensitive primary-to-secondary mirror separation, and a manually adjustable and lockable variable focus setting by changing the mirror separation. Critical gaps include 1) a 50-70 cm diameter primary mirror beam expander that features near-diffraction limited performance, low mass design, minimal aberrations with an emphasis on spherical, characterization of the polarization changes vs. beam cross section assuming input circular polarization, a lockable electronic focus adjustment, both built-in and removable fiducial aids for aligning the input laser beam to the optical axis, and a path to space qualification; and 2) a 15-cm diameter primary mirror beam expander with the same features for airborne coherent lidar systems.

Relevance / Science Traceability

Science Mission Directorate (SMD) desires both an airborne coherent-detection wind-profiling lidar systems and a space-based wind measurement. The space mission has been recommended to SMD by both the 2007 and 2017 earth science Decadal Surveys. SMD has incorporated the wind lidar mission in its planning and has named it "3-D Winds". SMD recently held the Earth Venture Suborbital competition for 5-years of airborne science campaigns. The existing coherent wind lidar at Langley, DAWN, was included in three proposals which are under review. Furthermore, SMD is baselining DAWN for a second CPEX-type airborne science campaign, and for providing cal/val assistance to the ESA AEOLUS space mission. DAWN flies on the DC-8 and it is highly desired to fit DAWN on other NASA and NOAA aircraft. DAWN needs to lower its mass for several of the aircraft, and a low-mass telescope retaining the required performance is needed. Additionally, an electronic remote control of telescope focus is needed to adapt to aircraft cruise altitude and weather conditions during science flights.

Scope Title
Fabrication, Test and Control of Advanced Optical Systems

Scope Description

Future UV/Optical/NIR telescopes require mirror systems that are very precise and ultra-stable.

Regarding precision, this subtopic encourages proposals to develop technology which makes a significant advance the ability to fabricate and test an optical system.

One area of current emphasis is the ability to non-destructively characterize CTE homogeneity in 4-m class Zerodur and 2-m class ULE mirror substrates to an uncertainty of 1 ppb/K and a spatial sampling of 100 x 100.  This characterization capability is needed to select mirror substrates before they undergo the expense of turning them into a light-weight space mirror.

Regarding stability, to achieve high-contrast imaging for exoplanet science using a coronagraph instrument, systems must maintain wavefront stability to < 10 pm RMS over intervals of ~10 minutes during critical observations. The ~10-minute time period of this stability is driven by current wavefront sensing and control techniques that rely on stellar photons from the target object to generate estimates of the system wavefront. This subtopic aims to develop new technologies and techniques for wavefront sensing, metrology, and verification and validation of optical system wavefront stability.

Current methods of wavefront sensing include image-based techniques such as phase retrieval, focal-plane contrast techniques such as electric field conjugation and speckle nulling, and low-order and out-of-band wavefront sensing that use non-science light rejected by the coronagraph to estimate drifts in the system wavefront during observations. These techniques are limited by the low stellar photon rates of the dim objects being observed (~5 - 11 Vmag), leading to 10s of minutes between wavefront control updates.

New methods may include: new techniques of using out-of-band light to improve sensing speed and spatial frequency content, new control laws incorporating feedback and feedforward for more optimal control, new algorithms for estimating absolute and relative wavefront changes, and the use of artificial guide stars for improved sensing signal to noise ratio and speed.

Current methods of metrology include edge sensors (capacitive, inductive, or optical) for maintaining segment cophasing, and laser distance interferometers for absolute measurement of system rigid body alignment. Development of these techniques to improve sensitivity, speed, and component reliability is desired. Low power, high-reliability electronics are also needed.

Finally, metrology techniques for system verification and validation at the picometer level during integration and test (I&T) are needed. High speed spatial and speckle interferometers are currently capable of measuring single-digit picometer displacements and deformations on small components in controlled environments. Extension of these techniques to large-scale optics and structures in typical I&T environments is needed.

References

The HabEx Interim Report is available at: https://www.jpl.nasa.gov/habex/pdf/interim_report.pdf [259]. The LUVOIR Interim Report is available at: https://asd.gsfc.nasa.gov/luvoir/resources/docs/LUVOIR_Interim_Report_Fi... [266].

Expected TRL or TRL range at completion of the project: 2 to 4

Desired Deliverables of Phase II

Analysis, Hardware, Software, Research

Desired Deliverables Description

An ideal Phase 1 deliverable would be a prototype demonstration of a fabrication, test or control technology leading to a successful Phase 2 delivery; or a reviewed preliminary design and manufacturing plan which demonstrates feasibility. While detailed analysis will be conducted in Phase 2, the preliminary design should address how optical, mechanical (static and dynamic) and thermal designs and performance analysis will be done to show compliance with all requirements. Past experience or technology demonstrations which support the design and manufacturing plans will be given appropriate weight in the evaluation.

An ideal Phase 2 project would further advance the technology to produce a flight-qualifiable relevant sub-component (with a TRL in the 4 to 5 range); or a working fabrication, test or control system. Phase 1 and Phase 2 mirror system or component deliverables would be accompanied by all necessary documentation, including the optical performance assessment and all data on processing and properties of its substrate materials. A successful mission oriented Phase 2 would have a credible plan to deliver for the allocated budget a fully assembled and tested telescope assembly which can be integrated into the potential mission; and, demonstrate an understanding of how the engineering specifications of their system meets the performance requirements and operational constraints of the mission (including mechanical and thermal stability analysis).

State of the Art and Critical Gaps

Wavefront sensing using star images, including dispersed-fringe and phase retrieval methods, is at TRL 6, qualified for space by JWST. Wavefront sensing and control for coronagraphs, including electric field conjugation and Low-Order WF Sensing (LOWFS) is at TRL4, and is being developed and demonstrated by WFIRST/CGI.

Laser distance interferometers for point-to-point measurements with accuracies from nanometers to picometers have been demonstrated on the ground by the Space Interferometry Mission and other projects, and on orbit by the Lisa Pathfinder and Grace Follow-On mission. Application to telescope alignment metrology has been demonstrated on testbeds, to TRL4 for nanometer accuracy. Picometer accuracy for telescopes awaits demonstration.

Edge sensors are in use on segmented ground telescopes, but not yet on space telescopes. New designs are needed to provide picometer sensitivity and millimeter range in a space qualified package.

Higher-order WFS for coronagraphs using out-of-band light is beginning development, with data limited to computer simulations. Such techniques are best used

Relevance / Science Traceability

These technologies are enabling for coronagraph-equipped space telescopes, segmented space telescopes, and others that utilize actively controlled optics. The LUVOIR and HabEx mission concepts currently under study provide good examples.

Scope Title
Optical Components and Systems for potential Infrared/Far-IR missions

Scope Description

The Far-IR Surveyor Mission described in NASA's Astrophysics Roadmap, "Enduring Quests, Daring Visions":

In the context of subtopic S2.03, the challenge is to take advantage of relaxed tolerances stemming from a requirement for long wavelength (30 micron) diffraction-limited performance in the fully-integrated optical telescope assembly to minimize the total mission cost through innovative design and material choices and novel approaches to fabrication, integration, and performance verification.

The Far-IR Surveyor is a cryogenic far-infrared mission, which could be either a large single-aperture telescope or an interferometer. There are many common and a few divergent optical system requirements between the two architectures.

Common requirements:

• Telescope operating temperature ~4 K
• Telescope diffraction-limited at 30 microns at the operating temperature
• Mirror survivability at temperatures ranging from 315 K to 4 K
• Mirror substrate thermal conductivity at 4 K > 2 W/m*K
• Zero or low CTE mismatch between mirror substrate and backplane

Divergent requirements:

• Large single-aperture telescope:
  • Segmented primary mirror, circular or hexagonal
  • Primary mirror diameter 5 to 10 m
  • Possible 3 dof (tip, tilt and piston) control of mirror segments on orbit
  • Interferometer:
    • Monolithic primary mirrors
    • Afocal, off-axis telescope design
    • Primary mirror diameter 1 to 4 m

Success metrics:

• Areal cost < $500K/m2
• Areal density < 15 kg/m2 (< 40 kg/m2 with backplane)
• Production rate > 2 m2 per month
• Short time span for optical system integration and test

References

The Far-Infrared Surveyor is described in NASA's Astrophysics Roadmap, "Enduring Quests, Daring Visions," which can be downloaded from https://smd-prod.s3.amazonaws.com/science-pink/s3fs-public/atoms/files/secure-Astrophysics_Roadmap_2013_0.pdf [253].

Program Annual Technology Reports (PATR) can be downloaded from the NASA PCOS/COR Technology Development website at https://apd440.gsfc.nasa.gov/technology/ [267].

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Hardware, Research

Desired Deliverables Description

Mirrors or optical systems that demonstrably advance TRL to address the overall challenge described under Scope Description while meeting requirements for a single-aperture or interferometric version of the notional Far-IR Surveyor mission.

State of the Art and Critical Gaps

Current SOA is represented by the Herschel Space Observatory (3.5 m monolith; SiC) and James Webb Space Telescope (6.5 m segmented primary mirror; beryllium).

Relevance / Science Traceability

The technology is relevant to the Far-IR Surveyor mission described in NASA's Astrophysics Roadmap and prioritized in NASA's Program Annual Technology Reports for Cosmic Origins and Physics of the Cosmos. A future NASA far-infrared astrophysics mission will answer compelling questions, such as: How common are life-bearing planets?; How do the conditions for habitability develop during the process of planet formation?; and How did the universe evolve in response to its changing ingredients (build-up of heavy elements and dust over time)? To answer these questions, NASA will need telescopes and interferometers that reach fundamental sensitivity limits imposed by astrophysical background photon noise. Only telescopes cooled to a cryogenic temperature can provide such sensitivity.

Novel approaches to fabrication and test developed for a far-infrared astrophysics mission may be applicable to far-infrared optical systems employed in other divisions of the NASA Science Mission Directorate, or to optical systems designed to operate at wavelengths shorter than the far-infrared.

Scope Title
Low-Cost Compact Reflective Telescope for NIR/SWIR Optical Communication

Scope Description

The need exists for a low cost methodology to produce compact (for ex., cubesat-class), scalable, diffraction limited, athermalized, off-axis reflective-type, optics for NIR/SWIR-band communication applications. Typically, specialty optical aperture systems are designed and built as “one-offs” which are inherently high in cost and often out of scope for smaller projects. A Phase I would investigate current compact off-axis reflective designs and develop a trade space to identify the most effective path forward. The work would include a strategy for aperture diameter scalability, athermalization, and low cost fabrication. Detailed optical designs would be developed along with detailed structural, thermal, optical performances (STOP) analyses confirming diffraction limited operation across a wide range of operational disturbances, both structural dynamic and thermal. Commercial of the shelf (COTS) NIR/SWIR optical communication support hardware should be assumed towards an integrated approach, including fiber optics, fast steering mirrors, and applicable detectors. Phase II may follow up with development of prototypes, built at multiple aperture diameters and fidelities.

References

An example of an on-axis design has been utilized in LLCD: https://www.spiedigitallibrary.org/conference-proceedings-of-spie/10563/105630X/NASAs-current-activities-in-free-space-optical-communications/10.1117/12.2304175.full?SSO=1 [268]

An example of an off-axis design is being developed by JPL for deep space optical comm (DSOC): https://www.spiedigitallibrary.org/conference-proceedings-of-spie/10096/100960V/Discovery-deep-space-optical-communications-DSOC-transceiver/10.1117/12.2256001.full [269]

Expected TRL or TRL range at completion of the project: 2 to 4

Desired Deliverables of Phase II

Prototype, Analysis, Hardware

Desired Deliverables Description

Prototype unobscured telescope with the required scale size

State of the Art and Critical Gaps

Currently, the state of the art for reflective optical system for communications applications are:

1)     On-axis or axisymmetric designs are typically used for (space) optical comm and imaging, which inherently are problematic due to the central obscuration.

2)     Off-axis designs provide superior optical performance due to the clear aperture, however, are rarely considered due to complex design, manufacturing, and metrology procedures needed.

Relevance / Science Traceability

Optical Communication enable high data-rate downlink of science data. The initial motivation for this scalable off-axis optical design approach is for bringing high-performance reflective optics within reach of laser communication projects with limited resources. However, this exact optical hardware is applicable for any diffraction limited, athermalized science imaging applications. Any science mission could potentially be able to select from a “catalog” of optical aperture systems that would already have (flight) heritage and reduced risks.

Scope Title
X-Ray Mirror Systems Technology, Coating Technology for X-Ray-UV-OIR, and Free-Form Optics

Scope Description

The National Academy Astro2010 Decadal Report identifies studies of optical components and ability to manufacture, coat, and perform metrology needed to enable future X-Ray observatory missions such as Next Generation of X-Ray Observatories (NGXO).

The Astrophysics Decadal specifically calls for optical coating technology investment for future UV, Optical, Exoplanet, and IR missions while Heliophysics 2009 Roadmap identifies the coating technology for space missions to enhance rejection of undesirable spectral lines, improve space/solar-flux durability of Extreme Ultraviolet (EUV) optical coatings, and coating deposition to increase the maximum spatial resolution.

Future optical systems for NASAs low-cost missions, CubeSat and other small-scale payloads, are moving away from traditional spherical optics to non-rotationally symmetric surfaces with anticipated benefits of freeform optics such as fast wide-field and distortion-free cameras.

This subtopic solicits proposals in the following three focus areas:

• X-Ray manufacturing, coating, testing, and assembling complete mirror systems in addition to maturing the current technology.
• Coating technology including Carbon Nanotubes (CNT) for wide range of wavelengths from X-Ray to IR (X-Ray, EUV, LUV, VUV, Visible, and IR).
• Free-form Optics design, fabrication, and metrology for CubeSat, SmallSat and various coronagraphic instruments.

References

The Habitable Exoplanet Observatory (HabEx) is a concept for a mission to directly image planetary systems around Sun-like stars. HabEx will be sensitive to all types of planets; however its main goal is, for the first time, to directly image Earth-like exoplanets, and characterize their atmospheric content. By measuring the spectra of these planets, HabEx will search for signatures of habitability such as water, and be sensitive to gases in the atmosphere possibility indicative of biological activity, such as oxygen or ozone.

The study pages are available at:

Habitable Exoplanet Observatory (HabEx): https://www.jpl.nasa.gov/habex/ [199]

LUVOIR: https://asd.gsfc.nasa.gov/luvoir/ [198]

Origins Space Telescope: https://asd.gsfc.nasa.gov/firs/ [221]

The LYNX Mission Concept: https://wwwastro.msfc.nasa.gov/lynx/ [200]

The Large UV/Optical/IR Surveyor (LUVOIR) is a concept for a highly capable, multi-wavelength space observatory with ambitious science goals. This mission would enable great leaps forward in a broad range of science, from the epoch of re-ionization, through galaxy formation and evolution, star and planet formation, to solar system remote sensing. LUVOIR also has the major goal of characterizing a wide range of exoplanets, including those that might be habitable - or even inhabited. The LUVOIR Interim Report is available at: https://asd.gsfc.nasa.gov/luvoir/ [198].

The Origins Space Telescope (OST) is the mission concept for the Far-IR Surveyor study. NASA's Astrophysics Roadmap, Enduring Quests, Daring Visions, recognized the need for an Origins Space Telescope mission with enhanced measurement capabilities relative to those of the Herschel Space Observatory, such as a three order of magnitude gain in sensitivity, angular resolution sufficient to overcome spatial confusion in deep cosmic surveys or to resolve protoplanetary disks, and new spectroscopic capability. The community report is available at: https://science.nasa.gov/science-committee/subcommittees/nac-astrophysics-subcommittee/astrophysics-roadmap [271]

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Typical deliverables based on sub-elements of this subtopic:

• X-ray optical mirror system: Analysis, reports, and prototype
• Coating: Analysis, reports, software, demonstration of the concept and prototype
• Freeform Optics: Analysis, design, software and hardware prototype of optical components

State of the Art and Critical Gaps

This subtopic focuses on three areas of technology development:

• X-Ray manufacturing, coating, testing, and assembling complete mirror systems in addition to maturing the current technology. This work is a very costly and time consuming. Most of SOA (State of the Art) requiring improvement is ~10 arc-seconds angular resolution. SOA straylight suppression is bulky and ineffective for wide-field of view telescopes. We seek significant reduction in both expense and time. Reduce the areal cost of telescope by 2x such that the larger collecting area can be produced for the same cost or half the cost.
• Coating technology for wide range of wavelengths from X-Ray to IR (X-Ray, EUV, LUV, VUV, Visible, and IR). The current X-ray coating is defined by NuSTAR. Current EV is defined by Heliophysics (80% reflectivity from 60-200 nm). Current UVOIR is defined by Hubble. MgFI2 over coated aluminum on 2.4 m mirror. This coating has birefringence concerns and marginally acceptable reflectivity between 100-200 nm.
• Free-form Optics design, fabrication, and metrology for package constrained imaging systems. This field is in early stages of development. Improving the optical surfaces with large field of view and fast F/#s is highly desirable.

Relevance / Science Traceability

S2.04 supports variety of Astrophysics Division missions. The technologies in this subtopic encompasses fields of X-Ray, coating technologies ranging from UV to IR, and Freeform optics in preparation for Decadal missions such as HabEx, LUVOIR and OST.

Optical components, systems, and stray light suppression for X-ray missions: The 2010 National Academy Decadal Report specifically identifies optical components and the ability to manufacture and perform precise metrology on them needed to enable several different future missions (NGXO). The NRC NASA Technology Roadmap Assessment ranked advanced mirror technology for new x-ray telescopes as the #1 Object C technology requiring NASA investment.

Freeform Optics: NASA missions with alternative low-cost science and small size payload are increasing. However, the traditional interferometric testing as a means of metrology are unsuited to freeform optical surfaces due to changing curvature and lack of symmetry. Metrology techniques for large fields of view and fast F/#s in small size instruments is highly desirable specifically if they could enable cost-effective manufacturing of these surfaces. (CubeSat, SmallSat, NanoSat, various coronagraphic instruments)

Coating for X-ray, EUV, LUV, UV, Visible, and IR telescopes: Astrophysics Decadal specifically calls for optical coating technology investment for: Future UV/Optical and Exoplanet missions (Habitable Exoplanet Observatory (HabEx) or Large Ultraviolet Optical Infrared Surveyor (LUVOIR)). Heliophysics 2009 Roadmap identifies optical coating technology investments for: Origins of Near-Earth Plasma (ONEP); Ion-Neutral Coupling in the Atmosphere (INCA); Dynamic Geospace Coupling (DGC); Fine-scale Advanced Coronal Transition-Region Spectrograph (FACTS); Reconnection and Micro-scale (RAM); & Solar-C Nulling polarimetry/coronagraph for exoplanet imaging and characterization, dust and debris disks, extra-galactic studies and relativistic and non-relativistic jet studies (VNC).

Scope Title
X-Ray Mirror Systems Technology

Scope Description

NASA large X-Ray observatory requires low-cost, ultra-stable, light-weight mirrors with high-reflectance optical coatings and effective stray light suppression. The current state-of-art of mirror fabrication technology for X-Ray missions is very expensive and time consuming. Additionally, a number of improvements such as 10 arc-second angular resolutions and 1 to 5 m2 collecting area are needed for this technology. Likewise, the stray-light suppression system is bulky and ineffective for wide-field of view telescopes.

In this area, we are looking to address the multiple technologies including: improvements to manufacturing (machining, rapid optical fabrication, slumping or replication technologies), improved metrology, performance prediction and testing techniques, active control of mirror shapes, new structures for holding and actively aligning of mirrors in a telescope assembly to enable X-Ray observatories while lowering the cost per square meter of collecting aperture and effective design of stray-light suppression in preparation for the Decadal Survey of 2020. Additionally, we need epoxies to bond mirrors that are made of silicon. The epoxies should absorb IR radiation with wavelengths between 1.5 um and 6 um that traverses silicon with little or no absorption, and therefore can be cured quickly with a beam of IR radiation. Currently, X-Ray space mirrors cost $4 million to $6 million per square meter of optical surface area. This research effort seeks a cost reduction for precision optical components by 5 to 50 times, to less than $1M to $100 K/m2.

Additionally, proposals are solicited to develop new advanced-technology Computer-Numerical-Control (CNC) machines to polish inside and/or outside surfaces of full-shell (between 100-1000mm in height, 100-2800mm in diameter, varying radial prescription along azimuth, and approximately 2mm in thickness), grazing-incidence optics to x-ray quality surface tolerances (with surface figure error < 1 arcsecond Half-Power Diameter (HPD), radial slope error < 1 microradian, and out of round < 2 microns). Current state-of-the-art technology in CNC polishing of full-shell, grazing-incidence optics yields 2.5 arcseconds HPD on the outside of a mandrel used for replicating shells.Technology advances beyond current state of the art include application of CNC and deterministic polishing techniques that (1) allow for direct force closed-loop control, (2) reduce alignment precision requirements, and (3) optimize the machine for polishing cylindrical optics through simplifying the axis arrangement and the layout of the cavity of the CNC polishing machine.

References

NASA High Energy Astrophysics (HEA) mission concepts including X-Ray missions and studies are available at https://heasarc.gsfc.nasa.gov/docs/heasarc/missions/concepts.html [272].

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Typical deliverable based on sub-elements of this subtopic:
X-ray optical mirror system: Demonstration, analysis, reports, software and hardware prototype

State of the Art and Critical Gaps

X-ray optics manufacturing, metrology, coating, testing, and assembling complete mirror systems in addition to maturing the current technology. This work is very costly and time-consuming. Most of SOA (State of the Art) requiring improvement is ~10 arc-seconds angular resolution. SOA straylight suppression is bulky and ineffective for wide-field of view telescopes. We seek a significant reduction in both expense and time. Reduce the areal cost of a telescope by 2x such that the larger collecting area can be produced for the same cost or half the cost.

The gaps to be covered in this track are:

• Light-weight, low-cost, ultra-stable mirrors for large X-ray observatory
• Stray light suppression systems (baffles) for large advanced X-Ray observatories
• Ultra-stable inexpensive light-weight X-Ray telescope using grazing-incidence optics for high altitude balloon-borne and rocket-borne mission

Relevance / Science Traceability

The 2010 National Academy Decadal Report specifically identifies optical components and the ability to manufacture and perform precise metrology on them needed to enable several different future missions (Lynx and Advanced X-ray Imaging Satellite (AXIS)).

The NRC NASA Technology Roadmap Assessment ranked advanced mirror technology for new x-ray telescopes as the #1 Object C technology requiring NASA investment.

Scope Title
Coating Technology for X-Ray-UV-OIR

Scope Description

The optical coating technology is a mission-enabling feature that enhances the optical performance and science return of a mission. Lowering the areal cost of coating determines if a proposed mission could be funded in the current cost environment. The most common forms of coating used on precision optics are anti-reflective (AR) coating and high reflective coating.

The current coating technology of optical components needed to support the 2020 Astrophysics Decadal process. Historically, it takes 10 years to mature mirror technology from TRL-3 to 6.
To achieve these objectives requires sustained systematic investment.

The telescope optical coating needs to meet low temperature operation requirement. It’s desirable to achieve 35 degrees Kelvin in future.

A number of future NASA missions require suppression of scattered light. For instance, the precision optical cube utilized in a beam-splitter application forms a knife-edge that is positioned within the optical system to split a single beam into two halves. The scattered light from the knife-edge could be suppressed by CNT coating. Similarly, the scattered light for gravitational-wave application and lasercom system where the simultaneous transmit/receive operation is required, could be achieved by highly absorbing coating such as CNT. Ideally, the application of CNT coating needs to achieve:

• Broadband (visible plus Near IR), reflectivity of 0.1% or less
• Resist bleaching of significant albedo changes over a mission life of at least 10 years
• Withstand launch conditions such vibe, acoustics, etc.
• Tolerate both high continuous wave (CW) and pulsed power and power densities without damage. ~10 W for CE and ~ 0.1 GW/cm2 density, and 1 kW/nanosecond pulses
• Adhere to the multi-layer dielectric or protected metal coating including Ion Beam Sputtering (IBS) coating

NASA's Laser Interferometer Space Antenna (LISA) mission on-axis design telescope operates both in transmission and reception simultaneously where the secondary mirror sends the transmitted beam directly back at the receiver. The apodized petal-shaped mask inherently suppress the diffraction once patterned at the center of the secondary mirror.  The emerging cryogenic etching of black-silicon has demonstrated BRDF ultralow specular reflectance of 1e-7 in the range of 500-1064 nm. The advancement of this technology is desired to obtain ultralow reflectivity.

• Improve the specular reflectance to 1e-10 and hemispherical reflectance better than 0.1%
• Improve the cryogenic etching process to provide a variation of the reflectance (apodization effect) by increasing or decreasing the height of the grass
• Explore etching process and duration

References

Laser Interferometer Space Antenna (LISA) is a space-based gravitational wave observatory building on the success of LISA Pathfinder and LIGO. Led by ESA, the new LISA mission (based on the 2017 L3 competition) is a collaboration of ESA and NASA.

More information could be found at https://lisa.nasa.gov [273]

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Coating: Analysis, reports, software, demonstration of the concept and prototype

State of the Art and Critical Gaps

Coating technology for wide range of wavelengths from X-Ray to IR (X-Ray, EUV, LUV, VUV, Visible, and IR).

• The current X-ray coating is defined by NuSTAR.
• Current EUV is defined by Heliophysics (80% reflectivity from 60-200 nm).
• Current UVOIR is defined by Hubble. MgFI2 over coated aluminum on 2.4 m mirror. This coating has birefringence concerns and marginally acceptable reflectivity between 100-200 nm.

Metrics for X-Ray:

• Multilayer high-reflectance coatings for hard X-Ray mirrors
• Multilayer Depth Gradient Coatings for 5 to 80 keV with high broadband reflectivity.
• Zero-net-stress coating of iridium or other high reflectance elements on thin substrates (< 0.5 mm)

Metrics for EUV:

• Reflectivity > 90% from 6 nm to 90 nm onto a < 2 meter mirror substrate.

Metrics for LUVOIR:

• Broadband Reflectivity > 70% from 90nm-120nm (LUV) and > 90% from 120nm-2.5um (VUV/Visible/IR).Reflectivity Non-uniformity < 1% 90nm-2.5um
• Induced polarization aberration < 1% 400nm-2.5um spectral range from mirror coating applicable to a 1-8m substrate

Metrics for LISA:

• HR: Reflectivity > 99% at 1064 +/- 2 nm with very low scattered light and polarization-independent performance over apertures of ~ 0.5 m.
• AR: Reflectivity < 0.005% at 1064 +/- 2 nm
  • Low-absorption, low-scatter, laser-line optical coatings at 1064nm
  • High reflectivity, R>0.9995
  • Performance in a space environment without significant degradation over time, due for example to radiation exposure or outgassing
  • High polarization purity, low optical birefringence over a range of incident angles from ~5 degrees to ~20 degrees
  • Low coating noise (thermal, photothermal, etc.) for high precision interferometric measurements
  • Ability to endure applied temperature gradients (without destructive effects, such as de-lamination from the substrate)
  • Ability to clean and protect the coatings and optical surfaces during mission integration and testing. Cleaning should not degrade the coating performance.

Non-stationary Optical Coatings:

• Used in reflection & transmission that vary with location on the optical surface.

Carbon Nanotube (CNT) Coatings

• Broadband Visible to NIR, Total Hemispherical Reflectivity of 0.01% or less, adhere to the multi-layer dielectric or protected metal coating

Black-Silicon Cryogenic Etching (New)

• Broadband UV+Visible+NIR+IR, Reflectivity of 0.01% or less, adhere to the multi-layer dielectric (silicon) or protected metal

Software tools to simulate, and assist the anisotropic etching by employing variety of modeling techniques such as Rigorous Coupled Wave Analysis (RCWA), Method of Moments (MOM), Finite-Difference Time Domain (FDTD), Finite Element Method (FEM), Transfer Matrix Method (TMM), and Effective Medium Theory (ETM).

Relevance / Science Traceability

Coating for X-ray, EUV, LUV, UV, Visible, and IR telescopes: Astrophysics Decadal specifically calls for optical coating technology investment for: Future UV/Optical and Exoplanet missions. Heliophysics 2009 Roadmap identifies optical coating technology investments for: Origins of Near-Earth Plasma (ONEP); Ion-Neutral Coupling in the Atmosphere (INCA); Dynamic Geospace Coupling (DGC); Fine-scale Advanced Coronal Transition-Region Spectrograph (FACTS); Reconnection and Micro-scale (RAM); & Solar-C.

LISA requires low scatter HR coatings and low reflectivity coatings for scatter suppression near 1064 nm. Polarization-independent performance is important.

Nulling polarimetry/coronagraph for Exoplanets imaging and characterization, dust and debris disks, extra-galactic studies and relativistic and non-relativistic jet studies (VNC).

Scope Title
Free-Form Optics

Scope Description

Future NASA science missions demand wider fields of view in a smaller package. These missions could benefit greatly by freeform optics as they provide non-rotationally symmetric optics which allow for better packaging while maintaining desired image quality. Currently, the design and fabrication of freeform surfaces is costly. Even though various techniques are being investigated to create complex optical surfaces, small-size missions highly desire efficient small packages with lower cost that increase the field of view and expand operational temperature range of un-obscured systems. In addition to the freeform fabrication, the metrology of freeform optical components is difficult and challenging due to the large departure from planar or spherical shapes accommodated by conventional interferometric testing. New methods such as multibeam low-coherence optical probe and slope sensitive optical probe are highly desirable.

Specific metrics are:

• Design: Innovative reflective optical designs with large fields of view (> 5 degrees) and fast F/#s
• Fabrication: 10 cm diameter optical surfaces (mirrors) with free form optical prescriptions with surface figure tolerances are 1-2 nm rms, and roughness < 5 Angstroms. Larger mirrors are also desired for flagship missions for UV and coronagraphy applications, with 10cm-1m diameter surfaces having figure tolerances <5nm RMS, and roughness <1 Angstroms RMS
• Metrology: Accurate metrology of ‘freeform’ optical components with large spherical departures (>1 mm), independent of requiring prescription specific null lenses or holograms.

References

A presentation on application of Freeform Optics at NASA is available at: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20170010419.pdf [274]

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Demonstration, analysis, design, software and hardware prototype of optical components

State of the Art and Critical Gaps

Free-form Optics design, fabrication, and metrology for package constrained imaging systems. This field is in early stages of development. Improving the optical surfaces with large field of view and fast F/#s is highly desirable.

Relevance / Science Traceability

NASA missions with alternative low-cost science and small size payload are increasing. However, the traditional interferometric testing as a means of metrology is unsuited to freeform optical surfaces due to changing curvature and lack of symmetry. Metrology techniques for large fields of view and fast F/#s in small size instruments are highly desirable specifically if they could enable cost-effective manufacturing of these surfaces. (CubeSat, SmallSat, and NanoSat). Additionally, design studies for large observatories such as OST and LUVOIR (currently being proposed for the 2020 Astrophysics Decadal Survey) have demonstrated improved optical performance over a larger field of view afforded by freeform optics. Such programs will require advances in freeform metrology to be successful.”

Scope Title
Components, assemblies, and subsystems for Extreme Precision Radial Velocity Measurements and Detection of Extrasolar Planets

Scope Description

Astronomical spectrographs have proven to be powerful tools for exoplanet searches. When a star experiences periodic motion due to the gravitational pull of an orbiting planet, its spectrum is Doppler-modulated in time. This is the basis for the Precision Radial Velocity (PRV) method, one of the first and most efficient techniques for detecting and characterizing exoplanets. Since spectrographs have their own drifts which must be separated from the periodic Doppler shift, a stable reference is always needed for calibration. Optical Frequency Combs (OFCs) and line-referenced etalons are capable of providing the instrument precision needed for detecting and characterizing Earth-like planets in the Habitable Zone of their Sun-like host stars. While “stellar jitter” (a star’s photospheric velocity contribution to the RV signal) is unavoidable, the contribution to the error budget from Earth’s atmosphere would be eliminated in future space missions. Thus, there is a need to develop robust spectral references with Size, Weight and Power (SWaP) suitable for space qualified operation to calibrate the next generation of high-resolution spectrographs with precision corresponding to < ~1 cm/s over multiple years of observations.

This subtopic solicits proposals to develop cost effective component and subsystem technology for low SWaP, long-lived, robust implementation of radial velocity measurement instruments both on the ground and in space. Research areas of interest include but are not limited to:

• Integrated photonic spectrographs
• PRV spectrograph calibration sources
• High efficiency photonic lanterns
• Advanced fiber scrambling techniques for modal noise reduction
• Software for advanced statistical techniques to mitigate effects of telluric absorption and stellar jitter on RV precision and accuracy

References

Precision Radial Velocity:

• Fischer et al. (2016) State of the Field: Extreme Precision Radial Velocities http://adsabs.harvard.edu/abs/2016PASP..128f6001 [276]
• Plavchan et al. (2015) Radial Velocity Prospects Current and Future: A White Paper Report prepared by the Study Analysis Group 8 for the Exoplanet Program Analysis Group (ExoPAG) http://adsabs.harvard.edu/abs/2015arXiv150301770P [277]
• Plavchan et al. (2019) EarthFinder Probe Mission Concept Study (Final Report): https://smd-prod.s3.amazonaws.com/science-red/s3fs-public/atoms/files/Ea... [278]

Photonic Lanterns:

• Gris-Sanchez et al. (2018) Multicore fibre photonic lanterns for precision radial velocity Science: https://academic.oup.com/mnras/article/475/3/3065/4769655 [279]
• Jvanovic, N. et al. (2012). Integrated photonic building blocks for next-generation astronomical instrumentation I: the multimode waveguide. Optics Express, 20:17029.

Astrocombs:

• Yi, X., et al. (2016) Demonstration of a near-IR line-referenced electro-optical laser frequency comb for precision radial velocity measurements in astronomy. Nature Communications, 7:10436.
• Halverson, S., et al, (2014) "The habitable-zone planet finder calibration system", Proc. SPIE 9147, Ground-based and Airborne Instrumentation for Astronomy V, 91477Z:  https://doi.org/10.1117/12.2054967 [280]
• Suh, M.-G., et al. (2019) Searching for exoplanets using a microresonator astrocomb. Nature Photonics, 13(1):25–30.
• Obrzud, E., et al. (2019) A Microphotonic Astrocomb. Nature Photonics, 13 (1):31–35.

Nonlinear Waveguides:

• Chang, L., et al. (2018) Heterogeneously integrated GaAs waveguides on insulator for efficient frequency conversion, Laser Photonics Reviews, 12, 1800149: https://doi.org/10.1002/lpor.201800149 [281]
• Halir, R., et al. (2012) Ultrabroadband supercontinuum generation in a CMOS-compatible platform, Optics letters, 37, 1685: https://di.org/10.1364/OL.37.001685 [282]

Spectral Flattening:

• Probst, R.A., et al. (2015) Spectrally Flattened, Broadband Astronomical Frequency Combs  https://di.org/10.1364/CLEO_SI.2015.SW4G.7 [283]

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Hardware/software

Desired Deliverables Description

This subtopic solicits proposals to develop cost effective component and subsystem technology for low SWaP, long-lived, robust implementation of radial velocity measurement instruments both on the ground and in space. Research areas of interest include but are not limited to:

• Integrated photonic spectrographs that meet PRV specifications (e.g. wavelength coverage, resolution, throughput, and polarization). These devices should be able to accept multiple fibers - at least two for the science light and simultaneous calibration light source. Ideally, they should be able to include on-chip cross-dispersion to eliminate bulk optics.
• PRV spectrograph calibration sources, particularly optical frequency combs (a.k.a. “astrocombs”) from the UV through the NIR (~350 nm – ~2400 nm) with ~10-30 GHz mode spacing, potentially self-referenced, or line stabilized for Allan Deviation <1E-11 over 100 seconds to years
  • Spectral flattening to provide uniform power across the spectral band covered by the instrument
  • Spectral broadening to obtain wide spectral coverage, preferably octave-spanning to enable self-referencing
  • Integrated photonic solutions including nonlinear waveguides, microresonators or other comb generators, pump lasers, and f-2f beat-note generation
  • Low phase-noise solutions
  • Tunability of comb lines to scan spectrograph detectors for pixel characterization
• Optical etalons with similar requirements for stability as the frequency combs
• High efficiency photonic lanterns
• Advanced fiber scrambling techniques for modal noise reduction
• Software for advanced statistical techniques to mitigate effects of telluric absorption and stellar jitter on RV precision and accuracy.

Proposals should show an understanding of the science needs, as well as present a feasible plan to fully develop the relevant subsystem technologies and to transition into future NASA program(s).

Phase I will emphasize research aspects for technical feasibility, infusion potential into ground or space operations, clear and achievable benefits (e.g., reduction in SWaP and/or cost, improved RV precision), and show a path towards a Phase II proposal. Phase I Deliverables include feasibility and concept of operations of the research topic, simulations and measurements, validation of the proposed approach to develop a given product (TRL 3-4), and a plan for further development of the specific capabilities or products to be performed in Phase II. Early development and delivery of prototype hardware/software is encouraged.

Phase II will emphasize hardware/software development with delivery of specific hardware or software products for NASA targeting demonstration operations at a ground-based telescope in coordination with the lead NASA center. Phase II deliverables include a working prototype or engineering model of the proposed product/platform or software, along with documentation of development, capabilities, and measurements (showing specific improvement metrics), documents and tools as necessary. Proposed prototypes shall demonstrate a path towards a flight-capable platform. Opportunities and plans should also be identified and summarized for potential commercialization or NASA infusion. 

State of the Art and Critical Gaps

The classical bulk optic spectrographs that are traditionally used for PRV science impose architectural constraints due to their large mass and limited optical flexibility. The spectrograph is the single element that if replaced with a photonic alternative could dramatically alter the course of astronomical instrumentation. Integrated Photonic Spectrographs (IPS) are wafer thin devices that could reduce instrument volume by up to three orders of magnitude. Furthermore, high resolving power spectrographs (R~150,000) with simultaneous UV, visible, and NIR coverage and exquisite long-term stability are required for PRV studies. Spectrometers that are fiber-fed with high illumination stability, excellent wavelength calibration, and precise temperature and pressure control represent the immediate future of precision RV measurements.

As spectrograph stability imposes limits on how precisely the Radial Velocity (RV) can be measured, spectral references play a critical role in characterizing and ensuring this precision. Only Laser Frequency Combs (LFCs) and line-referenced Fabry-Pérot etalons are capable of providing the broad spectral coverage and long term (years) stability needed for extreme PRV detection of exoplanets. While both frequency combs and etalons can deliver high precision spectrograph calibration, the former requires relatively complex and sophisticated hardware in the visible portion of the spectrum. Visible band frequency combs for astronomy (a.k.a. astrocombs) were initially based on mode-locked laser comb technology. However, the intrinsic free spectral range of these instruments, 100s of MHz to 1 GHz, is too fine to be resolved by astronomical spectrographs of R~150,000 or less. Thus, mode filtering of comb lines to create a more spectrally sparse calibration grid is necessary. The filtering step introduces complexity and additional sources of instability to the calibration process, as well as instrument assemblies too large in mass and volume for flight.

Commercial fiber laser astrocombs covering 450 - 1400 nm at 25 GHz line spacing and <3 dB intensity variations over the entire bandwidth are available for ground-based astronomical spectrographs and have been developed for HARPS-S and ESPRESSO RV instruments. However, the cost for these systems is often so prohibitive that recent RV spectrograph projects such as CARMENES and Keck Planet Finder either do not use a frequency comb or include it only as a future upgrade, owing to the cost impact on the project.

Alternatively, frequency combs produced by Electro-Optic Modulation (EOM) of a laser source have been demonstrated at observatories for PRV studies in the near-IR. EOM combs produce modes spaced at a RF modulation frequency, typically 10-30 GHz, and are inherently suitable as ground-based astrocombs. Significantly, EOM combs avoid the line filtering step of commercial mode-locked fiber laser combs. Comb frequency stabilization can be accomplished in a variety of ways, including referencing the laser pump source to a molecular absorption feature or another frequency comb. Where octave spanning EOM combs are available, f-2f self-referencing provides the greatest stability.

EOM combs must be spectrally broadened to provide the octave bandwidth necessary for f-2f stabilization for stability traceable to the Standard International (SI) second. This is accomplished through pulse amplification followed by injection into Highly Non-Linear Fiber (HNLF) or nonlinear optical waveguides, but the broadening process is accompanied by multiplication of the optical phase noise from the EOM comb modulation signal and must be optically filtered. Also, at these challenging microwave pulse repetition rates, the pulse duty-cycle requires pulse amplification to 4-5 Watts of average optical power in order to generate the high enough peak intensity needed for nonlinear broadening. This necessitates use of high power, non-telecom amplifiers that are more prone to lifetime issues, making EOM combs not optimal for flight either. It is important to note that very little comb light is actually required on the spectrograph detectors for calibration. In fact, most of the generated comb light must be deliberately attenuated to avoid detector saturation.

Power consumption of the frequency comb calibration system will be a significant driver of mission cost for space-based PRV systems, and motivates the development of a comb system that operates with less than 20 Watts of spacecraft power. Thus, for flight applications, it is highly desirable to develop frequency comb technology with low power consumption, ~10 GHz mode spacing, compact size, broad (octave spanning) spectral grasp across both the visible and NIR, phase noise insensitivity, stability traceable to the definition of the SI second, and very importantly, long life.

Relevance / Science Traceability

The NASA Strategic Plan (2018) and Space Mission Directorate Science Plan (2014) both call for discovery and characterization of habitable Earth analogs and the search for biosignatures on those worlds. These goals were endorsed and amplified upon in the recent National Academy of Science (NAS) Exoplanet Report which emphasized that a knowledge of the orbits and masses is essential to the complete and correct characterization of potentially habitable worlds. PRV measurements are needed to follow up on the transiting worlds discovered by Kepler, K2, and Transiting Exoplanet Survey Satellite (TESS). The interpretation of the transit spectra which James Webb Space Telescope (JWST) will obtain will depend on knowledge of a planet’s surface gravity which comes from its radius (from the transit data) and its mass (from PRV measurements or in some cases Transit Timing Variations). Without knowledge of a planet's mass, the interpretation of its spectrum is subject to many ambiguities.

These ambiguities will only be exacerbated for the direct imaging missions such as the proposed Habitable Exoplanet Observatory (HabEx) and Large Ultraviolet Optical Infrared Surveyor (LUVOIR) flagships which will obtain spectra of Earth analogs around a few tens to hundreds of stars. Even if a radius can be inferred from the planet's brightness and an estimate of its albedo, the lack of a dynamical mass precludes any knowledge of the planet's density, bulk composition, and surface gravity which are needed to determine, for example, absolute gas column densities. Moreover, a fully characterized orbit is challenging to determine from just a few direct images and may even be confused in the presence of multiple planets. Is a planet in a highly eccentric orbit habitable or not? Only dynamical (PRV) measurements can provide such information. Thus, highly precise and highly stable PRV measurements are absolutely critical to the complete characterization of habitable worlds.

The NAS report also noted that measurements from space might be a final option if the problem of telluric contamination cannot be solved. The Earth’s atmosphere will limit precise radial velocity measurements to ~10 cm/s at wavelengths longer than ~700 nm and greater than 30 cm/s at >900 nm, making it challenging to mitigate the effects of stellar activity without a measurement of the color dependence due to stellar activity in the PRV time series. A space-based PRV mission, such as has been suggested in the NASA EarthFinder mission concept study, may be necessary. If so, the low SWaP technologies developed under this SBIR program could help enable space-based implementations of the PRV method.

Scope Title
Planetary Aerial Vehicles for Venus

Scope Description

NASA is interested in scientific investigation of the Venus atmosphere and planetary surface using aerial vehicles. Aerial vehicles are expected to carry scientific payloads at Venus that will perform in-situ investigations of its atmosphere, surface and interior structure. The 2018 Venus Aerial Platforms Study report identified several key science investigations that are ideally suited to aerial platforms. The areas of scientific interest include: Atmospheric Gas Composition, Cloud and Haze Particle Characterization, Atmospheric Structure, Surface Imaging and Geophysical Investigations. Venus features a challenging atmospheric environment that significantly impacts the design of aerial vehicles. Proposals are sought in the following areas:

Aerial Vehicle Platforms for Venus - Concepts for Lighter-than-Air (e.g., balloons, airships) and Heavier-than-Air (e.g., fixed wing, rotary wing) vehicles are encouraged. The current state of the art in Venus aerial vehicles has been designed to operate within the altitude range of 50 to 60 km above the surface where the atmosphere is similar to the lower Earth atmosphere. The science objectives described in the Venus Aerial Platform study indicate that a wider range of altitudes is strongly desirable.

There are 3 areas of interest in this call:

1. Aerial systems that can maneuver throughout the range 40 to 70 km altitude for a long duration. The aerial platform should be able to operate on the sunlit side of Venus and be able to transit the night side and survive several circumnavigations around the planet. The proposal should describe how the vehicle concept would be deployed into the atmosphere and operated for its mission. The proposal does not have to address thermal design of the payload (if it is suspended under a balloon), but should include concepts for addressing the thermal requirements for the aerial platform. The atmospheric temperature ranges from 145C at 40 km to -10C at 60 km altitude. The aerial platform is not expected to operate extensively at the lower altitudes but should be capable of operating for short durations at high temperatures. Concepts for any of the following capabilities of aerial vehicle are encouraged:

• Technology demonstration with science payload less than 5 kg.
• Pathfinder mission with science payload less than 30 kg.
• Flagship mission with science payload up to 60 kg.

Other areas of interest include low cost approaches to:

1. Solar heated balloon systems to carry small science payloads (i.e. less than 10 kg payload) from 60 to 70 km altitude which would operate only on the sunlit side. These should be relatively simple systems that could operate collectively as a swarm system.
2. Deep atmospheric probes, deployed from aerial vehicles, to measure diurnal variations in the deep atmosphere of Venus. These could be deployed at different locations around Venus to capture atmospheric differences between day and night. Concepts for vehicles or neutrally buoyant probes that perform vertical descents, or guided/gliding descents to the surface are desired.

References

The Venus Aerial Platforms Study report can be found here: https://solarsystem.nasa.gov/resources/2197/aerial-platforms-for-the-scientific-exploration-of-venus/ [286]

Information about Venus can be found here: https://solarsystem.nasa.gov/planets/venus/in-depth/ [287]

Hall, J., Kerzhanovich, V., Fredrikson, T., Sandy, C., Pauken, M., Kulczycki, E....Day, S. (2017). Technology development for a Long Duration Mid-Cloud level Venus Balloon. Advances in Space Research Vol. 48 No. 7, 1238-1247.

Khatuntsev, I. V. (2017). Winds in the Middle Cloud Deck from the Near-IR. Journal of Geophysical Research: Planets. https://doi.org/10.1002/2017JE005355 [288]

Expected TRL or TRL range at completion of the project: 2 to 3

Desired Deliverables of Phase II

Prototype, Analysis, Research

Desired Deliverables Description

It is expected that a Phase I effort will consist of a system-level design and a proof-of-concept experiment on one or more key components.

Deliverables shall be a final report describing the results of the concept analysis, demonstration of any key technology developed and photos of any prototypes that were built and tested.

State of the Art and Critical Gaps

Terrestrial based aerial vehicles, including lighter-than-air and heavier-than-air are mature technologies and continue making advancements in capability, reliability and autonomy. But these need adaptation for operation in the Venus environment.

A gap exists in aerial vehicle technology that allows for variable altitude investigation in the Venus atmospheric environment. Floating at a fixed altitude means the vehicle is basically collecting samples of the same atmosphere each time it performs a collection since it floats with the wind. Having variable altitude capability allows significantly better investigation into the atmospheric structure. Variable altitude balloon concepts have been developed to operate over the altitude range of 50 to 60 km. New science goals defined in the Venus Aerial Platforms Study have indicated that stretching this operating range over 40 to 60 km is needed. This is a significant challenge because of the high atmospheric temperature at the 40 km altitude.

Relevance / Science Traceability

Relevance: Applied Physics Laboratory’s (APL) Dragonfly mission selection by New Frontiers shows there is significant interest in aerial vehicles for science investigations. It is in NASA's interests through the SBIR program to continue fostering innovative ideas to develop mission concepts to explore Venus using aerial vehicles.

JPL's Solar System Mission Formulation Office and the NASA Science Mission Directorate's Planetary Science Division advocate Venus aerial vehicle platform development. Furthermore, there are many enthusiastic supporters of exploring other worlds with aerial platforms throughout NASA.

Science Traceability: The 2018 Venus Aerial Platforms Study report identified several key science investigations that are ideally suited to aerial platforms. The areas of scientific interest include: Atmospheric Gas Composition, Cloud and Haze Particle Characterization, Atmospheric Structure, Surface Imaging and Geophysical Investigations. The variable altitude aerial vehicle platform is ideal for investigating these science goals and objectives.

Scope Title
Satellite Communications for Balloons

Scope Description

Improved downlink bitrates and innovative solutions using satellite relay communications from balloon payloads are needed. Long duration balloon flights currently utilize satellite communication systems to relay science and operations data from the balloon to ground based control centers. The current maximum downlink bit rate is 150 kilobits per second operating continuously during the balloon flight. Future requirements are for bit rates of 1 megabits per second or more. Improvements in bit rate performance, reduction in size and mass of existing systems, or reductions in cost of high bit rate systems are needed. Tracking and Data Relay Satellite (TDRSS) and Iridium satellite communications are currently used for balloon payload applications. A commercial S-band TDRSS transceiver and a mechanically steered 18 dBi gain antenna provide 150 kbps continuous downlink. TDRSS K-band transceivers are available but are currently cost prohibitive. Open port Iridium service is also in use, but the operational cost is high per byte transferred.

References

NASA's SuperTIGER Balloon Flies Again to Study Heavy Cosmic Particles:https://sites.wff.nasa.gov/code820/ [289]

Expected TRL or TRL range at completion of the project: 1 to 3

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Desired deliverables include results of analysis or simulation, or test results of actual prototype hardware and/or software. Phase II deliverables could include a prototype that could be test flown on a balloon mission.

State of the Art and Critical Gaps

Current commercially available satellite relays systems that could be used for balloon flight are either too costly, or do not provide the needed downlink data rates.

Relevance / Science Traceability

Science Mission Directorate (SMD) - NASA HQ (Astrophysics Division). Enables multiple Research Opportunities in Space and Earth Science (ROSES) opportunities, Small Explorer (SMEX) Announcement of Opportunity (AO) (Astrophysics), Astrophysics Mission of Opportunity, Hands-On Project Experience (HOPE) (annually). Improvements to satellite communications for research balloons would enable greater and better data collection, possibly extended flight duration, and other such potential benefits.

Scope Title
Helium Replenishment System

Scope Description

NASA long duration Super Pressure Balloons (SPB) are large and complex structures that contain seams and fittings. Since these balloons are hand constructed, there is potential for gas loss due to leaks through the seams or fittings, or permeation through the balloon envelope that is made of linear low-density polyethylene. In the event of a gas loss, a helium replenishment system is needed to augment the lifting gas in order to increase the likelihood of payload recovery overland, and to extend the flight duration. The desired system shall not significantly affect the overall mass of the payload and shall require limited power for efficient operation.

References

NASA's SuperTIGER Balloon Flies Again to Study Heavy Cosmic Particles:https://sites.wff.nasa.gov/code820/ [289]

Expected TRL or TRL range at completion of the project: 1 to 3

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Desired deliverables include results of analysis or simulation, or test results of actual prototype hardware and/or software. Phase II deliverables could include a prototype that could be test flown on a balloon mission.

State of the Art and Critical Gaps

No such system currently exists.

Relevance / Science Traceability

SMD - NASA HQ (Astrophysics Division). Enables multiple ROSES opportunities, Small Explorer (SMEX) Announcement of Opportunity (AO) (Astrophysics), Astrophysics Mission of Opportunity, Hands-On Project Experience (HOPE) (annually). A replenishment system can potentially prove very beneficial for avoiding payload termination over water by extending flight duration and enabling payload recovery overland in case of limited gas loss. This in turn can result in salvaging high value science data and payload recovery. Such a system can also possibly extend flight duration enabling more science data collection as well as other such potential benefits.

Scope Description

NASA's space based observatories, fly-by spacecraft, orbiters, landers, and robotic and sample return missions, require robust command and control capabilities. Advances in technologies relevant to command and data handling and instrument electronics are sought to support NASA's goals and several missions and projects under development.

The 2020 subtopic goals are to develop platforms for the implementation of miniaturized highly integrated avionics and instrument electronics that:

• Are consistent with the performance requirements for NASA missions.
• Minimize required mass/volume/power as well as development cost/schedule resources.
• Can operate reliably in the expected thermal and radiation environments.

Successful proposal concepts should significantly advance the state-of-the-art. Furthermore, proposals developing hardware should indicate an understanding of the intended operating environment, including temperature and radiation. Note that environmental requirements vary significantly from mission to mission. For example, some low earth orbit missions have a total ionizing dose (TID) radiation requirement of less than 10 krad(Si), while planetary missions can have requirements well in excess of 1 Mrad(Si).

Specific technologies sought by this subtopic include:

Fault-tolerant computing: Processor and eco-system (ASIC & Design IP) designed to mitigate single event upsets (SEUs) – Technologies are sought that implement fault tolerant computers leveraging industry standard processor instruction set architectures (ISPIAs) and interfaces. Although not limited to, there is particular interest in leveraging the reduced instruction set computer (RISC) principles of RISC-V architecture. Offerors should identify coding language of IP cores, use of architecture specific modules which would limit the ability to swap hardware chipsets, options for scaling fault tolerance, code/gate size and features versus power and speed. Offerors working application-specific integrated circuit (ASIC) efforts should identify possible foundries and their radiation tolerance processes. Offerors offering processing units should identify operating system / toolchain support. Offerors proposing design intellectual property (IP) should identify mitigation technique(s) including burdens on code development time / hardware performance and size.

Multiple output point of load power regulator: This module, preferably implemented utilizing one or more controller ASICs, will source a minimum of 3 settable output voltages when provided with standard spacecraft power bus input. Output voltages shall be independently settable to any voltage between 3.3V and .9 V with efficiency of at least 95%. Regulation, noise filtering and other operational specifications should be commensurate with industry standards for space-based systems. Output current in the 10A range to handle field-programmable gate array (FPGA) core requirements. The module should provide standard spacecraft power supply features, including over voltage protection, fault tolerance, load monitoring, sequencing, synchronization, soft start and should allow control and status monitoring by a remote power system controller. Using fewer external components is also highly desirable. There is also interest in a capability to provide data over power line communication to the converter for control and monitoring functions. The offeror should determine radiation tolerance levels achievable utilizing commercially available processes and indicate, in the proposal, the radiation tolerance goals.

High density high-reliability interconnections: A high reliability connector or interconnect mechanism that can operate in space environments (vacuum, vibration) and deliver hundreds of signal/power connections while using as little physical board area as possible is desired. The design should handle everything from carrying power to high speed (10+ Gbps) impedance controlled connections. The design should be scalable in different sizes to accommodate fewer connections and save board space. Low insertion force is desirable. Right angle and stacking design options should be considered.

References

For descriptions of radiation effects in electronics, the proposer may visit (http://radhome.gsfc.nasa.gov/radhome/overview.htm [291]).   

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Hardware, Software

Desired Deliverables Description

Desired Phase 2 deliverables for fault tolerant computing architectures are IP cores / ASIC designs implemented using an appropriate hardware design language (VHDL or Verilog) that have been demonstrated as an integrated system. Any required system software should be available, preferably as open source, to provide compilers, debuggers, and operating systems to the architecture. The fault tolerance of the architecture should be demonstrated.

Desired Phase 2 deliverable for the multiple output point of load switcher is a prototype multi-output point of load regulator. The regulator should be integrated onto a test board and be performance tested under varying resistive, capacitive, and transient load conditions.

Desired Phase 2 deliverables for the high density high-reliability interconnect are prototypes of the connection system (different size, orientations, etc.). The connector should be integrated onto a test board where its performance (speed, cross talk, etc.) can be verified. 

State of the Art and Critical Gaps

There is a need for a broader range of offerings for fault tolerant computing architectures. This includes the need for viable options between performance, size (gate count) and power tradeoffs. There are currently a few sources of fault tolerant computing, and additional variety would help reduce costs for future NASA missions. Fault tolerant computing enables robust autonomous systems to be designed and implemented. Furthermore, recent commercial processor architecture developments offer improved performance and a broader array of performance options, and fault tolerant variants of these could significantly benefit NASA missions.

There are multiple output point of load converters available from commercial companies. The existing commercial parts require many external components eliminating their space savings. Commercial parts are not built on radiation tolerant processes.

Current connectors are too large, especially for small satellites and CubeSats. As the size of the printed circuit boards has shrunk, the percent of board space being used by the I/O connectors has become unacceptable. The connectors are taking away from circuitry and sensors that could be providing additional functionality and science products. High density commercial connectors also tend to be lacking in their general ruggedness, outgassing, and ability to prevent intermittent connections in high vibration environments like orbital launches.

Relevance / Science Traceability

Fault tolerant / autonomous computing architectures are relevant to increasing science return and lowering costs for missions across all Science Mission Directorate (SMD) divisions. However, the benefits are most significant for miniaturized instruments and subsystems that must operate in harsh environments. These missions include interplanetary CubeSats and smallsats, outer planets instruments, and heliophysics missions to harsh radiation environments. For these missions, the inherent fault tolerance would provide an additional level of protection on top of the radiation tolerance of the FPGA or ASIC on which the computing system is implemented. Additionally, for missions with large communication delays, the inherent fault tolerance can limit the need for ground intervention.

Multi-output point of load converters and high-density high-reliability interconnects are relevant to miniaturizing electronics. Miniaturized flight electronics allows one to fit more functionality into less volume, allowing smaller spacecraft to perform science that was previously done by larger satellites. These missions include interplanetary CubeSats and smallsats, outer planets instruments, and heliophysics missions.

Scope Description

This subtopic addresses NASA's need to develop technologies for producing space systems that can operate without environmental protection housing in the extreme environments of NASA missions. Key performance parameters of interest are survivability and operation under the following conditions:

1)     Very low temperature environments (e.g., temperatures at the surface of Titan and of other Ocean Worlds as low as -180 deg C; and in permanently shadowed craters on the Moon), or

2)     Combination of low temperature and radiation environments (e.g., surface conditions at Europa of -180 deg C with very high radiation), or

3)     Very high temperature, high pressure and chemically corrosive environments (e.g., Venus surface conditions having very high pressure and temperature of 486 deg C).

NASA is interested in expanding its ability to explore the deep atmospheres and surfaces of planets, asteroids, and comets through the use of long-lived (days or weeks) balloons and landers. Survivability in extreme high temperatures and high pressures is also required for deep atmospheric probes to the giant planets. Proposals are sought for technologies that are suitable for remote sensing applications at cryogenic temperatures, and in-situ atmospheric and surface explorations in the high temperature, high pressure environment at the Venusian surface (485°C, 93 atmospheres), or in low-temperature environments such as those of Titan (-180°C), Europa (-220°C), Ganymede (-200°C), Mars, the Moon, asteroids, comets and other small bodies. Also, Europa-Jupiter missions may have a mission life of 10 years and the radiation environment is estimated at 2.9 Mega-rad total ionizing dose (TID) behind 0.1 inch thick aluminum. Proposals are sought for technologies that enable NASA's long duration missions to extreme wide-temperature and cosmic radiation environments. High reliability, ease of maintenance, low volume, low mass, and low out-gassing characteristics are highly desirable. Special interest lies in development of the following technologies that are suitable for the environments discussed above:

• Wide temperature range precision mechanisms, e.g., beam steering, scanner, linear and tilting multi-axis mechanisms
• Radiation-tolerant/radiation-hardened low-power, low-noise, mixed-signal mechanism control electronics for precision actuators and sensors
• Wide temperature range feedback sensors with sub-arcsecond/nanometer precision
• Long life, long stroke, low power, and high torque force actuators with sub-arc-second/nanometer precision
• Long life bearings/tribological surfaces/lubricants
• High temperature energy storage systems
• High-temperature actuators and gear boxes for robotic arms and other mechanisms
• Low-power and wide-operating-temperature radiation-tolerant/ radiation hardened RF electronics
• Radiation-tolerant/radiation-hardened low-power/ultra-low power, wide-operating-temperature, low-noise mixed-signal electronics for space-borne systems such as guidance and navigation avionics and instruments
• Radiation-tolerant/radiation-hardened power electronics
• Radiation-tolerant/radiation-hardened electronic packaging (including shielding, passives, connectors, wiring harness and materials used in advanced electronics assembly)

Research should be conducted to demonstrate technical feasibility during Phase I and show a path toward a Phase II hardware demonstration, and when possible, deliver a demonstration unit for functional and environmental testing at the completion of the Phase II contract.

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

References

1. Proceedings of the Extreme Environment Sessions of the IEEE Aerospace Conference. https://www.aeroconf.org/ [293] or via IEEE Xplore Digital Library
2. Proceedings of the meetings of the Venus Exploration Analysis Group (VEXAG). https://www.lpi.usra.edu/vexag/ [294]
3. Proceedings of the meetings of the Outer Planet Assessment Group (OPAG). https://www.lpi.usra.edu/opag/ [295]

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Hardware

Desired Deliverables Description

Deliverables include proof of concept working prototypes that demonstrate the innovations defined in the proposal and enable direct operation in extreme environments.

State of the Art and Critical Gaps

Future NASA missions to high priority targets in our solar system will require systems that have to operate at extreme environmental conditions. NASA missions to the surfaces of Europa and other Ocean Worlds bodies will be exposed to temperatures as low as -180 deg C and radiation levels that are at megarad levels. Operation in permanently shadowed craters on the Moon is also a region of particular interest. In addition, NASA missions to the Venus surface and deep atmospheric probes to Jupiter or Saturn will be exposed to high temperatures, high pressures, and chemically corrosive environments.

Current state-of-practice for development of space systems for the above missions is to place hardware developed with conventional technologies into bulky and power-inefficient environmentally protected housings. The use of environmental protection housing will severely increase the mass of the space system, limit the life of the mission and the corresponding science return. This solicitation seeks to change the state of the practice by support technologies that will enable development of lightweight, highly efficient systems that can readily survive and operate in these extreme environments without the need for the environmental protection systems.

Relevance / Science Traceability

Relevance to SMD (Science Mission Directorate) is high.

Low temperature survivability is required for surface missions to Titan (-180 deg C), Europa (-220 deg C), Ganymede (-200 deg C), small bodies and comets. Mars diurnal temperatures range from -120 deg C to +20 deg C. For the Europa Clipper baseline concept, with a mission life of 10 years, the radiation environment is estimated at 2.9 megarad total ionizing dose (TID) behind 100 mil thick aluminum. Lunar equatorial region temperatures swing from -180 deg C to +130 deg C during the lunar day/night cycle, and shadowed lunar pole temperatures can drop to -230 deg C.

Advanced technologies for high temperature systems (electronics, electro-mechanical and mechanical) and pressure vessels are needed to ensure NASA can meet its long duration (days instead of hours) life target for its science missions which operate in high temperature and high pressure environments.

Scope Description

The planetary protection and contamination control subtopic focuses on mission-enabling and capability-driven technologies to improve NASA's ability to prevent forward and backward contamination. Forward contamination is the transfer of viable organisms from Earth to another body. Backward contamination is the transfer of material posing a biological threat back to Earth's biosphere. NASA is seeking innovative technologies or applications of technologies to facilitate meeting portions of forward and backward contamination requirements to include:

• Improvements to spacecraft cleaning and sterilization that remain compatible with spacecraft materials and assemblies,
• Prevention of re-contamination and cross-contamination throughout the spacecraft lifecycle,
• Improvements to detection and verification of organic compounds and biologicals on spacecraft, to include microbial detection and assessments for viable organism and DNA-based verification technologies to encompass sampling devices, sample processing, and sample analysis pipelines, and
• Active in-situ recontamination/decontamination approaches (e.g., in-situ heating of sample containers to drive off volatiles prior to sample collection) and in-situ/in-flight sterilization approaches (e.g., UV or plasma) for surfaces.
• Enabling end-to-end sample return functions to assure containment and pristine preservation of materials gathered on NASA missions.

For contamination control efforts, understanding contaminants and preventing contamination supports the preservation of sample science integrity and ensures spacecraft function nominally. NASA is seeking analytical and physics-based modeling technologies and techniques to quantify and validate sub-micron particulate contamination, low energy surface material coatings to prevent contamination, and modeling and analysis of particles to ensure hardware and instrumentation meet organic contamination requirements.

Examples of Outcomes

• End-to-end microbial reduction/sterilization technology for larger spacecraft subsystems
• Microbial reduction/sterilization technology for spacecraft components
• Ground/based biological contamination/re-contamination mitigation system that can withstand spacecraft assembly and testing operations
• In-flight spacecraft component-to-component cross contamination mitigation system
• Viable organism and/or DNA sample collection devices, sample processing (e.g. low biomass extraction), and sample analysis (e.g. bioinformatic pipelines for low biomass)
• Real-time, rapid device for detection and monitoring of viable organism contamination on low biomass surfaces or in cleanroom air
• Bioburden spacecraft cleanliness monitors for assessing surface cleanliness throughout flight and surface operations during missions
• DNA-based system to elucidate abundance, diversity, and planetary protection relevant functionality of microbes present on spacecraft surfaces
• An applied molecular identification technology to tag/label biological contamination on outbound spacecraft
• Low surface area energy coatings
• Molecular adsorbers (“getters”)
• Experimental technologies for measurement of outgassing rates lower than 1.0E-15 g/cm2/s with mass-spectrometry, under flight conditions (low and high operating temperatures) and with combined exposure to natural environment (e.g., high-energy radiation, ultraviolet radiation, atomic oxygen exposure)
• Physics-based technologies for particulate transport modeling and analysis for continuum, rarefied and molecular flow environments, with electrostatic, vibro-acoustic, particle detachment and attachment capabilities
• Modeling and analysis technologies for view-factor computation technologies for complex geometries with articulation (e.g., rotating solar arrays, articulating robotic arms)

References

Planetary Protection: https://planetaryprotection.nasa.gov/ [297]
 Handbook for the Microbial Examination of Space Hardware:  https://searchworks.stanford.edu/view/2569630 [298]   

Expected TRL or TRL range at completion of the project 2 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Technologies, approaches, techniques, models, and/or prototypes including accompanying data validation reports demonstrating how the product will enable spacecraft compliance with planetary protection and contamination control requirements.

State of the Art and Critical Gaps

Planetary protection state-of-the-art leverages the technologies resulting from the 1960s-1970s Viking spacecraft assembly and test era. The predominant means to control biological contamination on spacecraft surfaces is using some combination of heat microbial reduction processing, solvent cleaning (e.g. isopropyl alcohol cleaning). Notably, vapor hydrogen peroxide is a NASA approved process, but the variability of the hydrogen peroxide concentration, delivery mechanism, and material compatibility concerns still tends to be a hurdle to infuse it on a flight mission with complex hardware and multiple materials for a given component. Upon microbial reduction the hardware then is protected in a cleanroom environment (ISO 8 or better) using protective coverings when hardware is not being assembled or tested. Biological cleanliness is then verified through the NASA standard assay which is a culture-based method. Rapid cleanliness assessments can be performed, but are not currently accepted as a verification methodology, to inform engineering staff about biological cleanliness during critical hardware assembly or tests which include the total adenosine triphosphate (tATP) and limulus amoebocyte lysate (LAL) assays. Terminal sterilization has been conducted with recontamination prevention for in-flight biobarriers employed for the entire spacecraft (Viking) or a spacecraft subsystem (Phoenix spacecraft arm). In addition to the hardware developed approaches for compliance environmental assessments are implemented to understand recontamination potential for cleanroom surfaces and air. While the NASA standard assay is performed on the cleanroom surfaces DNA-based methodologies have been adopted to include 16S and 18S rRNA targeted sequencing while metagenomic approaches are currently undergoing development. Thus, the critical planetary protection gaps include the assessment of DNA from low biomass surfaces (<0.1 ng/uL DNA using current technologies from 1-5m2 of surface), sampling devices that are suitable for low biomass and compounds (e.g. viable organisms, DNA) but also compliant with cleanroom and electrostatic discharge limits, quantification of the widest spectrum of viable organisms, enhanced microbial reduction / sterilization modalities that are compatible with flight materials and a ground- and flight-based recontamination systems.

Contamination Control requirements and practices are also evolving rapidly as mission science objectives targeting detection of organics and life are driving stricter requirements and improved characterization of flight system and science instrument induced contamination. State-of-the-art Contamination Control includes:

• Testing and measurement of outgassing rates down to 3.0E-15 g/cm2/s with mass-spectrometry, under flight conditions (low and high operating temperatures) and with combined exposure to natural environment (high-energy radiation, ultraviolet radiation, atomic oxygen exposure)
• Particulate transport modeling and analysis for continuum, rarefied and molecular flow environments with electrostatic, vibro-acoustic, particle detachment and attachment capabilities.
• Modeling and analysis of molecular return flux using Direct Simulation Monte Carlo (DSMC) and the BGK formulation.

Relevance / Science Traceability

Planetary protection requirements has emerged in recent years with increased interest in investigating bodies with the potential for life detection such as Europa, Enceladus, Mars, etc. and the potential for sample return from such bodies. The development of such technologies would enable missions to be able to be responsive to planetary protection requirements as they would be able to assess viable organisms and establish microbial reduction technologies to achieve acceptable microbial bioburden levels for sensitive life detection instruments to prevent inadvertent “false positives,” to ensure compliance sample return planetary protection and science requirements, and to provide a means to comply with probabilistic based planetary protection requirements for biologically sensitive missions (e.g. outer planets and sample return).

Scope Title

Avionics Computing Support

Scope Description

The NASA State-Of-the-Art (SOA) in space computing utilizes 20-year-old technology and is inadequate for future missions. In conjunction with the United States Air Force (USAF), NASA is investing in the development of the High-Performance Spaceflight Computing (HPSC) Chiplet, a radiation-hardened multi-core processor that will improve space computing capabilities by two orders of magnitude. Another joint NASA-USAF project will develop rad-hard, high capacity, high-speed memory components that will likewise improve space computing capabilities by approximately two orders of magnitude.  And yet another project, with a planned start date of FY 2019, will start developing a single board computer based on an HPSC-chiplet.

While these efforts will provide an underlying platform, they do not provide the full range of advanced computing capabilities that will be required to support missions currently in the planning stage for the mid-2020s and beyond. Topics of interest include:

• HPSC-compatible Coprocessors: General purpose neural networks and other machine learning accelerators for robotic vision, system health management, and similar applications are needed to meet performance: power requirements in future autonomous robotic systems. Initial design of this application-specific integrated circuit (ASIC) and a validated field-programmable gate arrays (FPGA) implementation of critical portions of the design is desired. A successful SBIR will potentially lead to a Phase 3 award, or alternate funding, to implement the final chiplet.
• Fault Tolerant, Real Time Linux: A flight qualifiable version of Linux for the HPSC Chiplet, capable of supporting parallel and heterogeneous processing for autonomy, robotics and science codes is desired. Initial design of a verifiably reliable, fault tolerant, real time Linux kernel is desired. A successful SBIR will potentially result in a Phase 3 award, or alternate funding, to develop a complete, qualified, operating system.
• Compilers that support Software Implemented Fault Tolerance (SIFT) capabilities (e.g., control flow checking, coordinated checkpoint/rollback, recovery block) for the HPSC Chiplet is desired. A successful SBIR will potentially result in a Phase 3 award, or alternate funding, to implement a complete SIFT-capable software development system.
• Fault tolerant middleware to Support HPSC Chiplet Parallel Processing: Includes math and I/O libraries to support robotic capabilities, autonomy and science processing, and including library routines for Neon Single instruction, Multiple Data (SIMD) processors as well as A53 general purpose processors.
• Technology and languages to enable development of provably correct software.
• Radiation tolerant standard cell libraries for processes below 28nm that are suitable for NASA missions in the natural space environment.

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers.  Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future. In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

References

https://www.nasa.gov/press-release/goddard/2017/nasa-selects-high-performance-spaceflight-computing-hpsc-processor-contractor [300]

Expected TRL or TRL range at completion of the project: 4 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software

Desired Deliverables Description

For hardware elements, a preliminary design ready for detailed design, fabrication, and production.

State of the Art and Critical Gaps

The SOA in space qualifiable high performance computing has high power dissipation (approximately 18 W) and the SOP in TRL-9 space computing have relatively low performance (between 2 DMIPS to 200 DMIPS at 100 MHz). Neither of these systems provides the performance, power:performance ratio, or the flexibility in configuration, performance, power management, fault tolerance, or extensibility with respect to heterogeneous processor elements. The HPSC Chiplet, currently in development, will provide significantly enhanced capabilities but, as currently defined, lacks a broad range of coprocessors and accelerators (which are supported in the architecture but not planned for implementation) as well as software elements that will be required for use in future missions. This lack of hardware and software ecosystem elements is the focus of this nomination.

Relevance / Science Traceability

HPSC ecosystem is of interest to all major programs in HEOMD (Human Exploration and Operations Mission Directorate) and SMD (Science Mission Directorate). We have had discussions with program and project managers across NASA. Immediate infusion targets include Mars Fetch Rover, WFIRST/Chronograph, Gateway, and SPLICE/Lunar Lander.

Scope Title
Hot Structure Technology for Aerospace Vehicles

Scope Description

This subtopic encompasses the development of reusable hot structure technology for structural components exposed to extreme heating environments on aerospace vehicles. A hot structure system is a multi-functional structure that can reduce or eliminate the need for a separate thermal protection system (TPS) or active cooling system. The potential advantages of using a hot structure system in place of a TPS with underlying cool structure are: reduced mass, increased mission capability, such as reusability, improved aerodynamics, improved structural efficiency and increased ability to inspect the structure.  Hot structure is an enabling technology for reusability between missions or mission phases, such as aerocapture followed by entry, and has been used in prior NASA programs (Space Shuttle Orbiter, Hyper-X, and X-37) on control surfaces and wing leading edges, as well as in Department of Defense programs.  Additionally, the development of hot structure technology for combustion-device liquid rocket engine propulsion systems is of great interest.

This subtopic seeks to develop innovative low-cost, damage tolerant, reusable and lightweight hot structure technology applicable to aerospace vehicles exposed to extreme temperatures between 1093° to 2204°C (2000° to 4000°F). These aerospace vehicle applications are unique in requiring the hot structure to carry primary structure vehicle loads and to be reusable after exposure to extreme temperatures during atmospheric entry and/or liquid rocket engine firings. The material systems of interest for use in developing hot structure technology include:  advanced carbon-carbon (C-C) materials, ceramic matrix composites (CMC’s), or advanced high-temperature refractory metals.  Potential applications of hot structure technology include: primary load-carrying aeroshell structures, control surfaces, leading edges, and propulsion system components (such as hot gas valves, combustion chambers, and passively- or actively-cooled nozzle extensions).

Proposals should present approaches to address the current need for improvements in operating temperature capability, toughness/durability, reusability and material system properties. Focus areas should address one or more of the following:

• Improvements in manufacturing processes and/or material designs to achieve repeatable and uniform material properties that should be scalable to actual vehicle components: specifically, material property data obtained from flat-panel test coupons should represent the properties of prototype and flight test articles.
• Material/structural architectures and multifunctional systems providing significant improvements over typical 2D inter-laminar mechanical properties while maintaining in-plane and thermal properties when compared to state-of-the-art C-C or CMC materials.  Examples include:  incorporating through-the-thickness stitching, braiding or 3D woven preforms.
• Functionally-graded manufacturing approaches to optimize oxidation protection, damage tolerance and structural efficiency, in an integrated hot structure concept that extends performance for multiple cycles up to 2204°C (4000°F).
• Manufacturing process methods that enable a significant reduction in the time required to fabricate materials and components.  There is a great need to reduce processing time for hot structure materials and components -- current state-of-the-art fabrication times are often in the range of 6 to 12 months, which can limit the use of such materials.  Approaches enabling reduced manufacturing times should not, however, lead to significant reductions in material properties.

Under this subtopic, research, testing, and analysis should be conducted to demonstrate technical feasibility during Phase I and show a path towards Phase II hardware demonstrations. Phase I feasibility studies should also address cost and risk associated with the hot structures technology. At the completion of the Phase I project, in addition to the final report, deliverables should include at least one of the following to aid assessment of technical feasibility: (a) coupons appropriate for thermal and/or mechanical material property tests, (b) arc-jet test specimens, or (c) a subscale nozzle extension test article or analog component. Emphasis should be placed on the delivery of manufacturing demonstration units for NASA testing at the completion of the Phase II contract. In addition, Phase II studies should address scale-up and integration with vehicles that could make use of the developed technology.

Hot structure technology is relevant to the Human Exploration and Operations Mission Directorate (HEOMD), where the technology can be infused into spacecraft and launch vehicle applications. Such technology should provide either improved performance or enable advanced missions requiring re-usability, increased damage tolerance and the durability to withstand long-term space exploration missions. The ability to allow for delivery of larger payloads to various space destinations, such as the lunar south pole, is also of great interest.

The Advanced Exploration Systems (AES) Program would be ideal for further funding a prototype hot structure system and technology demonstration effort. Commercial Space programs, such as Commercial Orbital Transportation Services (COTS), Commercial Lunar Payload Services (CLPS), and Next Space Technologies for Exploration Partnerships (NextSTEP), are also interested in this technology for flight vehicles. Additionally, NASA HEOMD programs that could use this technology include the Space Launch System (SLS) and the Human Landing System (HLS) for propulsion applications.

Potential NASA users of this technology exist for a variety of propulsion systems, including the following:

• Upper stage engine systems, such as those for the Space Launch System,
• In-space propulsion systems, including nuclear thermal propulsion systems,
• Lunar/Mars lander descent/ascent propulsion systems,
• Solid motor systems, including those for primary propulsion, hot gas valve applications, and small separation and/or attitude-control systems, and
• Propulsion systems for the Commercial Space industry, which is supporting NASA efforts.

Finally, the U.S. Air Force is interested in such technology for its Evolved Expendable Launch Vehicle (EELV), ballistic missile and hypersonic vehicle programs. Other non-NASA users include the U.S. Navy, the U.S. Army, the Missile Defense Agency (MDA) and the Defense Advanced Research Projects Agency (DARPA). The subject technology can be both enhancing to systems already in use or under development, as well as enabling for applications that may not be feasible without further advancements in high temperature composite technology.

References

Hypersonic Hot Structures:

Glass, David. "Ceramic matrix composite (CMC) thermal protection systems (TPS) and hot structures for hypersonic vehicles." 15th AIAA International Space Planes and Hypersonic Systems and Technologies Conference. 2008.

Walker, Sandra P., et al. "A Multifunctional Hot Structure Heat Shield Concept for Planetary Entry." 20th AIAA International Space Planes and Hypersonic Systems and Technologies Conference. 2015.

Liquid Rocket Propulsion systems:

“Carbon-Carbon Nozzle Extension Development in Support of In-Space and Upper-Stage Liquid Rocket Engines” paper; Paul R. Gradl and Peter G. Valentine; 53rd AIAA/SAE/ASEE Joint Propulsion Conference, Atlanta, GA; AIAA-2017-5064; July 2017; https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20170008949.pdf [302].

“Carbon-Carbon Nozzle Extension Development in Support of In-Space and Upper Stage Liquid Rocket Engines” presentation charts; Paul R. Gradl and Peter G. Valentine; 53rd AIAA/SAE/ASEE Joint Propulsion Conference, Atlanta, GA; AIAA-2017-5064; July 2017; https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20170008945.pdf [303].

Note: The above references are open literature references. Other references exist regarding this technology, but they are International Traffic in Arms Regulations (ITAR) restricted. Numerous online references exist for the subject technology and projects/applications noted, both foreign and domestic.

Expected TRL or TRL range at completion of the project: 2 to 4

Desired Deliverables of Phase II

Prototypes or components suitable for testing by NASA or Commercial Space partners.

Desired Deliverables Description

At the completion of Phase I project deliverables should include at least one of the following:  coupons appropriate for thermal/mechanical material property tests, arc-jet test specimens, or a subscale nozzle extension test article. Emphasis should be on the delivery of manufacturing demonstration units, with representative structural features, for NASA testing at the completion of the Phase II contract.

State of the Art and Critical Gaps

The current state of the art for composite hot structure components is limited primarily to applications with maximum use temperatures in the 1093° – 1600°C (2000° – 2912°F) range. While short excursions to higher temperatures are possible, considerable degradation may occur. Reusability is limited and may require considerable inspection before reuse. Critical gaps or technology needs include:  (a) increasing operating temperatures to 1700° – 2204+°C (3092° – 4000+°F); (b) increasing resistance to environmental attack (primarily oxidation); (c) increasing manufacturing technology capabilities to improve reliability, repeatability and quality control; (d) increasing durability/toughness and interlaminar mechanical properties (or introducing 3D architectures); and (e) decreasing overall manufacturing time required.

As an alternative to composites, metallic hot structures may reduce operating temperature requirements to near 1000°C (1832°F) in some applications, while offering greater structural reliability, and should also be pursued. Unfortunately advancements in high temperature metals have been a significant gap.

Relevance / Science Traceability

Hot structure technology is relevant to the Human Exploration and Operations Mission Directorate (HEOMD), where the technology can be infused into spacecraft and launch vehicle applications. Such technology should provide either improved performance or enable advanced missions requiring reusability, increased damage tolerance and the durability to withstand long-term space exploration missions. The ability to allow for delivery of larger payloads to various space destinations, such as the lunar south pole, is also of great interest.

The Advanced Exploration Systems (AES) Program would be ideal for further funding a prototype hot structure system and technology demonstration effort. Commercial Space programs, such as Commercial Orbital Transportation Services (COTS), Commercial Lunar Payload Services (CLPS), and Next Space Technologies for Exploration Partnerships (NextSTEP), also are interested in this technology for flight vehicles. Additionally, NASA HEOMD programs that could use this technology include the Space Launch System (SLS) and the Human Landing System (HLS) for propulsion applications.

Potential NASA users of this technology exist for a variety of propulsion systems, including the following:

• Upper stage engine systems, such as those for the Space Launch System,
• In-space propulsion systems, including nuclear thermal propulsion systems,
• Lunar/Mars lander descent/ascent propulsion systems,
• Solid motor systems, including those for primary propulsion, hot gas valve applications and small separation and/or attitude-control systems, and
• Propulsion systems for the Commercial Space industry, which is supporting NASA efforts.

Finally, the U.S. Air Force is interested in such technology for its Evolved Expendable Launch Vehicle (EELV), ballistic missile, and hypersonic vehicle programs. Other non-NASA users include the U.S. Navy, the U.S. Army, the Missile Defense Agency (MDA), and the Defense Advanced Research Projects Agency (DARPA). The subject technology can be both enhancing to systems already in use or under development, as well as enabling for applications that may not be feasible without further advancements in high temperature composite technology.

Scope Description

NASA human and robotic missions to the surface of planetary or airless bodies require Entry, Descent, and Landing (EDL). For many of these missions, EDL represents one of the riskiest phases of the mission. Despite the criticality of the EDL phase, NASA has historically gathered limited engineering data from such missions, and use of the data for real-time Guidance, Navigation and Control (GN&C) during EDL for precise landing (aside from Earth) has also been limited. Recent notable exceptions are the Orion EFT-1 flight test, Mars Entry, Descent, & Landing Instrument (MEDLI) sensor suite, and the planned sensor capabilities for Mars 2020 (MEDLI2 and map-relative navigation). NASA requires EDL sensors to: a) understand the in-situ entry environment b) characterize the performance of entry vehicles, and c) make autonomous and real-time onboard GN&C decisions to ensure a precise landing.

This subtopic describes three related technology areas where innovative sensor technologies would enable or enhance future NASA EDL missions. Proposers may submit solutions to any of these scope areas:

1)     High Accuracy, Light Weight, Low Power Fiber Optic or Recession Sensing System for Thermal Protection Systems.

2)     Miniaturized Spectrometers for Vacuum Ultraviolet & Mid-wave Infrared In-Situ Radiation Measurements during Atmospheric Entry.

3)     Novel Sensing Technologies for EDL GN&C and Small-Body Proximity Operations.

NASA seeks innovative sensor technologies to enable and characterize entry, descent and landing operations on missions to planetary and airless bodies. This subtopic describes three related technology areas where innovative sensor technologies would enable or enhance future NASA EDL missions. Candidate solutions are sought that can be made compatible with the environmental conditions of deep spaceflight, and the rigors of landing on planetary bodies both with and without atmospheres. Proposers may submit to scope areas 1, 2 or 3 below.

1) HIGH ACCURACY, LIGHT WEIGHT, LOW POWER FIBER OPTIC OR RECESSION SENSING SYSTEM FOR THERMAL PROTECTION SYSTEMS.

Current NASA state-of-the-art EDL sensing systems are very expensive to design and incorporate on planetary missions. Commercial fiber optic systems offer an alternative that could result in a lower overall cost and weight, while actually increasing the number of measurements. Fiber optic systems are also immune to Electro-magnetic Interference (EMI) which reduces design and qualification efforts. This would be highly beneficial to future planetary missions requiring Thermal Protection Systems (TPS). In addition, as NASA looks to the future of science missions to the Outer Planets, extreme entry environments will require the new, 3-D woven Heatshield for Extreme Entry Environment Technology (HEEET) TPS recently matured within the Agency. Gathering flight performance data on this new material will be key, particularly the measurement of recession, which was so very important on the Galileo probe mission to Jupiter. Minimizing the sensor intrusion of the outer mold line is critical in this case, because the extreme environment dictates that the TPS be as aerothermally monolithic as possible. In applications to planetary entry vehicles greater than about 1 m diameter, however, the HEEET TPS is expected to contain seams that might be used for accommodating instrumentation. Recession measurements in carbon fiber/phenolic TPS systems like Phenolic Impregnated Carbon Ablator (PICA) and AVCOAT are also of interest. When ablation is not severe and/or rapid, accurate measurements have proven difficult with the historic Galileo-type sensor, which was based on the differential resistance resulting from sensor materials that have charred.

The upcoming Mars 2020 mission will fly the Mars Entry, Descent, and Landing Instrumentation II (MEDLI2) sensor suite consisting of a total of 24 thermocouples, 8 pressure transducers, 2 heat flux sensors, and a radiometer embedded in the TPS. This set of instrumentation will directly inform the large performance uncertainties that contribute to the design and validation of a Mars entry system. A better understanding of the entry environment and TPS performance could lead to reduced design margins enabling a greater payload mass fraction and smaller landing ellipses. Fiber optic sensing systems can offer benefits over traditional sensing system like MEDLI and MEDLI2, and can be used for both rigid and flexible TPS. Fiber optic sensing benefits include, but are not limited to; sensor immunity to EMI, the ability to have thousands of measurements per fiber using Fiber Bragg Grating (FBG), multiple types of measurements per fiber (i.e. temperature, strain, and pressure), and resistance to metallic corrosion.

To be considered against NASA state-of-the-art TPS sensing systems for future flight missions, fiber optic systems must be competitive in sensing capability (measurement type, accuracy, quantity), and Sensor Support Electronics (SSE) mass, size and power. Therefore NASA is looking for a fiber optic system that can meet the following requirements:

Sensing Requirements

• TPS Temperature: Measurement Range: -200 to 1250C (up to 2000C preferred), Accuracy: +/- 5C desired.
• Surface Pressure: Measurement Range: 0-15 psi, Accuracy: < +/-0.5%

Sensor Support Electronics Requirements (including enclosure):

• Weight: 12 lbs or less,
• Size: 240 cubic inches or smaller,
• Power: 15W or less,
• Measurement Resolution: 14-bit or Higher,
• Acquisition Rate per Measurement: 16 Hz or Higher.
• Compatibility with all sensors types, e.g., Temperature, Pressure, Heat Flux, Strain, Radiometer, TPS recession.

For recession measurements in extreme entry environments requiring 3-D woven TPS, NASA is seeking novel concepts that fit into the sensor/electronics architecture described above, and meet the following requirements:

• Up to 5000 W/cm2 heat flux,
• Up to 5 atmospheres of pressure on the vehicle surface,
• Recession measurement accuracy within +/- 1 mm.

For recession measurements in moderate entry environments requiring carbon fiber/phenolic TPS systems, NASA is seeking novel concepts that fit into the sensor/electronics architecture described above, and meet the following requirements:

• Up to 150-2000 W/cm2 heat flux,
• Up to 1 atmosphere of pressure on the vehicle surface,
• Recession measurement accuracy within +/- 1 mm.

2) MINIATURIZED SPECTROMETERS FOR VACUUM ULTRAVIOLET & MID-WAVE INFRARED RADIATION IN-SITU MEASUREMENTS DURING ATMOSPHERIC ENTRY

The current state-of-the-art for flight radiation measurements includes radiometers and spectrometers. Radiometers can measure heating integrated over a wide wavelength range (e.g. MEDLI2 Radiometer), or over narrow-wavelength bands (COMARS+ ICOTOM at 2900 nm and 4500 nm). Spectrometers gather spectrally resolved signal and have been developed for Orion EM-2 (combined Ocean Optics STS units with a range of 190-1100 nm). A spectrometer provides the gold standard for improving predictive models and improving future entry vehicle designs.

For NASA missions through CO2 atmospheres (Venus and Mars), a majority of the radiative heating occurs in the Midwave Infrared range (MWIR: 1500 nm - 6000 nm) [Brandis]. Similarly, for entries to Earth, the radiation is dominated by the Vacuum Ultraviolet (VUV) range (VUV: 100 - 190 nm) [Cruden]. Both of these ranges are outside of those detectable by available miniaturized spectrometers. While laboratory-scale spectrometers and detectors are available to measure these spectral ranges, there are no versions of these spectrometers which would be suitable for integration into a flight vehicle due to lack of miniaturization. This SBIR calls for miniaturization of VUV and Mid-Wave Infrared (MWIR) spectrometers to extend the current state of the art for flight diagnostics.

Advancements in either VUV or MWIR measurements are sought, preferably for sensors with:

• Self-contained with a maximum dimension of ~10 cm or less,
• No active liquid cooling,
• Simple interfaces compatible with spacecraft electronics, such as RS232, RS422, or Spacewire,
• Survival to military spec temperature ranges [-55 to 125C],
• Power usage of order 5W or less.

3) NOVEL SENSING TECHNOLOGIES FOR EDL GN&C AND SMALL BODY PROXIMITY OPERATIONS

NASA seeks innovative sensor technologies to enhance success for EDL operations on missions to other planetary bodies (including Earth's Moon, Mars, Venus, Titan, and Europa). Sensor technologies are also desired to enhance proximity operations (including sampling and landing) on small bodies such as asteroids and comets.

Sensing technologies are desired that determine any number of the following:

• Terrain relative translational state (altimetry/3-axis velocimetry).
• Spacecraft absolute state in planetary/small-body frame (either attitude, translation, or both).
• Terrain characterization (e.g., 3D point cloud) for hazard detection, absolute and/or relative state estimation, landing/sampling site selection, and/or body shape characterization.
• Wind-relative vehicle state and environment during atmospheric entry (e.g., velocity, density, surface pressure, temperature).

Successful candidate sensor technologies can address this call by:

• Extending the dynamic range over which such measurements are collected (e.g., providing a single surface topology sensor that works over a large altitude range such as 1m to >10km, and high attitude rates such as greater than 45° /sec).
• Improving the state-of-the-art in measurement accuracy/precision/resolution for the above sensor needs.
  * Substantially reducing the amount of external processing needed by the host vehicle to calculate the measurements.
• Significantly reducing the impact of incorporating such sensors on the spacecraft in terms of Size, Weight, and Power (SWaP), spacecraft accommodation complexity, and/or cost.
• Providing sensors that are robust to environmental dust/sand/illumination effects.
• Mitigation technologies for dust/particle contamination of optical surfaces such as sensor optics, with possible extensibility to solar panels and thermal surfaces for Lunar, asteroid, and comet missions.
• Sensing for wind-relative vehicle velocity, local atmospheric density, and vehicle aerodynamics (e.g. surface pressures and temperatures).

NASA is also looking for high-fidelity real-time simulation and stimulation of passive and active optical sensors for computer vision at update rates greater than 2 Hz to be used for signal injection in terrestrial spacecraft system test beds. These solutions are to be focused on improving system-level performance Verification and Validation during spacecraft assembly and test.

References

Brandis, A., Cruden, B., White, T., Saunders, D., and Johnston, C. Radiative Heating on the After-Body of Martian Entry Vehicles, AIAA 2015-3111, 45th AIAA Thermophysics Conference, Dallas, TX, 22-26 June 2015.

Cruden, B., Martinez, R., Grinstead, J., and Olejniczak, J. Simultaneous Vacuum-Ultraviolet Through Near-IR Absolute Radiation Measurement with Spatiotemporal Resolution in An Electric Arc Shock Tube, AIAA 2009-4240, 41st AIAA Thermophysics Conference, San Antonio, TX, 22-25 June 2009.

Johnston, C. and Brandis, A. Features of Afterbody Radiative Heating for Earth Entry, Journal of Spacecraft and Rockets, Vol. 52, Issue 1, 15 December 2014.

Expected TRL or TRL range at completion of the project: 3 to 5

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Depending on the type of technology submissions, hardware demonstrations of sensors or applicable support hardware (e.g. EDL sensors), or software simulations/analysis of simulated environments (simulation environments for passive and active optical sensors) are acceptable.

State of the Art and Critical Gaps

Active and passive GN&C EDL sensor technologies have been in development over the past decade. Infusion of these capabilities into spaceflight missions requires additional technology advancements to enhance operational performance and dynamic envelop, reduce size, mass, and power, and to address the process of space qualification.

The EDL community has a need to understand the specific contributors to aftbody radiation (especially in CO2 and air); a spectrometer is the next logical step beyond the current state-of-the-art radiometers for EFT-1 and MEDLI2. NASA now requires instrumentation on SMD competed missions involving EDL, and these cost- and mass-constrained missions cannot use the SOA instrumentation. The specific need is for miniaturized spectrometers for in-situ measurements with sensitivity in the VUV or MWIR regions where NASA predicts significant radiation for Earth, Venus, and Mars entries. VUV spectrometers require window operation under vacuum conditions with UV-grade windows for detection of the vacuum ultraviolet. The window materials become increasingly exotic as lower wavelengths are sought. The dispersion of wavelength becomes reduced as spectrometers shrink, which may become an issue for closely spaced features at lower wavelength. Extending the range of miniaturized spectrometers into the MWIR may be limited by the need for extensive cooling and as long wavelengths approach the diffraction limit.

Relevance / Science Traceability

EDL instrumentation directly informs and addresses the large performance uncertainties that drive the design, validation and in-flight performance of planetary entry systems. Improved understanding of entry environments and TPS performance could lead to reduced design margins enabling a greater payload mass-fraction and smaller landing ellipses. Improved real-time measurement knowledge during entry could also minimize the landing dispersions for placing advanced payloads onto the surface of atmospheric and airless bodies.

NASA Science missions are frequently proposed, that include high-speed Earth return (New Frontiers, Discovery, and Mars Sample Return) and Venus and Mars entry. Capsules used for these missions must withstand both convective and radiative aeroheating, and NASA now requires EDL instrumentation for these missions. Current radiative measurement techniques (radiometers) provide only an integrated heating over limited wavelength range; past interpretation of such flight data [Johnston] show the need for spectrally resolved measurements from spectrometers. For Earth and Venus, the radiative component may be the dominant source of heating, and emission comes from the VUV, that NASA currently has no capability to measure. For Mars and Venus, the aftbody radiation is dominated by MWIR. Again, NASA does not have a method to measure MWIR radiation in flight; the current radiometers integrate across several band systems. Miniaturized spectrometers that can measure in VUV and MWIR would have immediate application to SMD planetary missions. Such spectrometers may also inform what ablation species are emitted from the heatshield and backshell during entry.

Scope Title
Deployable Aerodynamic Decelerator Technology

Scope Description

Background: NASA is advancing deployable aerodynamic decelerators to enhance and enable robotic and human space missions. Applications include Mars, Venus, Titan, as well as payload return to Earth from Low Earth Orbit. The benefit of deployable decelerators is that the entry vehicle structure and thermal protection system is not constrained by the launch vehicle shroud. It has the flexibility to more efficiently use the available shroud volume, and can be packed into a much smaller volume for Earth departure, addressing potential constraints for payloads sharing a launch vehicle. For Mars, this technology enables delivery of very large (20 metric tons or more) usable payload, which may be needed to support human exploration. The technology also allows for reduced cost access to space by enabling the recovery of launch vehicle assets. This subtopic area solicits innovative technology solutions applicable to deployable entry concepts. Specific technology development areas include:

1) Advancements in textile manufacturing technologies that can be used to simplify production, reduce the mass, or reduce the stowed volume of mechanically deployed structures, inflatable structures, or their flexible thermal protection system. Thermal protection concepts can also lead to improvements in thermal management efficiency of radiant and conductive heat transport at elevated temperatures (exceeding 1200 C). Concepts can be either passive or active dissipation approaches. For smaller scale inflatable systems, less than 1.5 meters in diameter, thin-ply or thin-film manufacturing approaches that can be used to reduce the minimum design gauge are of particular interest for inflatable structures. Focus of Phase 1 development can be subscale manufacturing demonstrations that demonstrate proof of concept and lead to Phase 2 manufacturing scale-up for applications related to Mars entry, Earth return, launch asset recovery, or the emergent small satellite community.

2) Concepts designed to augment the drag or provide guidance control for any class of entry vehicle. Concepts can be either deployable or rigid design systems that are suitable to deployable vehicle designs, including methods that modulate vehicle symmetry or adjust lift for active flight control to improve landing accuracy. Designs that decrease the ballistic coefficient by a factor of two to three times are to be considered. Of particular interest are concepts that can be used to modulate the lift or drag of a vehicle for enhanced control. Phase I proof of concept and preliminary design efforts that will lead to, or can be integrated into, flight demonstration prototypes in a Phase 2 effort are of interest.

3) High temperature capable structural elements to support mechanically deployable decelerators that surpass the performance capability of metallic ribs, joints, and struts. Anticipated systems would include composite elements or hybrid approaches that combine metallic structures with high temperature capable interface materials to improve thermal performance. Phase 1 development can be subscale component demonstrations that lead to Phase 2 scale-up and testing in relevant environments.

References

Hughes, S. J., et al, “Hypersonic Inflatable Aerodynamic Decelerator (HIAD) Technology Development Overview,” AIAA Paper 2011-2524

Bose, D. M, et al, “The Hypersonic Inflatable Aerodynamic Decelerator (HIAD) Mission Applications Study,” AIAA Paper 2013-1389

Hollis, B. R., “Boundary-Layer Transition and Surface Heating Measurements on a Hypersonic Inflatable Aerodynamic Decelerator with Simulated Flexible TPS,” AIAA Paper 2017-3122

Cassell, A., et al, “ADEPT, A Mechanically Deployable Re-Entry Vehicle System, Enabling Interplanetary CubeSat and Small Satellite Missions,” SSC18-XII-08, 32nd Annual AIAA/USU Conference on Small Satellites

Expected TRL or TRL range at completion of the project: 1 to 4

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Subscale manufacturing demonstration articles for Phase I that can lead to Phase II manufacturing scale up.

State of the Art and Critical Gaps

The current state of the art for deployable aerodynamic decelerators is limited due to novelty of this technology. Developing more efficient, lighter, and thinner flexible thermal protection system component materials with higher temperature capability could potentially enable more efficient designs and extend the maximum range of use of the concepts. Development of efficient guidance control and drag enhancements concepts for deployable vehicles is enabling technology. Novel and innovative high temperature structural concepts are needed for the mechanically deployed decelerator.

Relevance / Science Traceability

NASA needs advanced deployable aerodynamic decelerators to enhance and enable robotic and human space missions. Applications include Mars, Venus, Titan, as well as payload return to Earth from Low Earth Orbit. HEOMD (Human Exploration and Operations Mission Directorate), STMD (Space Technology Mission Directorate), and SMD (Science Mission Directorate) can benefit from this technology for various exploration missions.

Scope Description

Plume/Surface Interaction Analysis & Ground Testing

As NASA and commercial entities prepare to land robotic and crewed vehicles on the Moon, and eventually Mars, characterization of landing environments is critical to identifying requirements for landing systems and engine configurations, instrument placement and protection, and landing stability. The ability to model and predict the extent to which regolith is transported in the vicinity of the lander is also critical to understanding the effects on precision landing sensor requirements and landed assets located in close proximity. Knowledge of the characteristics, behavior, and trajectories of ejected particles and surface erosion during the landing phase is important for designing descent sensor systems that will be effective. Furthermore, although the physics of the atmosphere, gravitational field, and the characteristics of the regolith are different for the Moon, the tools and analysis capability to characterize plume/surface interactions on the Moon will feed forward to Mars.

Therefore, NASA is seeking support in the following areas:

1. To increase analysis capability to model and predict the plume/surface interaction and nature and behavior of the ejecta, for NASA and commercial landing. Currently, there are negligible amounts of data collected from planetary robotic landings to develop and validate plume/surface interaction analysis tools. However, the limited data increase the understanding of various parameters, including the various types of surfaces that lead to different cratering effects and plume behaviors. Additionally, the information influences lander design and operations decisions for future missions. Ground testing (“unit tests”) is also used to provide data for tool validation. Innovative non-intrusive diagnostic development to measure critical parameters in this discipline are also severely lacking and are needed to advance prediction capability. The current post-landing analysis of planetary landers (on Mars) is of limited applicability in reducing risk to future landers, as it is limited to comparisons with only partially empirically-validated tools. Flight test data do not yet exist in the environments of interest.
2. The community needs ground test and flight test data, together with comprehensive Computational Fluid Dynamics (CFD) tools and methods, to devise validated models for different conditions that are applicable to a variety of landing missions. A consistent tool set is important for assessing risk and is useful to both the commercial sector and NASA.
3. Solutions are sought to alleviate the plume-surface interaction environment.  Solutions should provide novel approaches for propulsion cluster placements, surface ejecta damage tolerant systems, mitigation shielding, etc. These solutions must be mass-efficient and have minimal interference with vehicle operations.
4. Validation data and diagnostic techniques at relevant scales, environments, and degrees of system integration are sought to reduce uncertainties in predicted plume-induced environments and subsequently reduce risk to landers and other surface assets.  Critical parameters include near-field and far-field particle velocity, trajectories and concentration, erosion rates and transient crater profiles. There are large uncertainties associated with these parameters. Plume-induced environments include cratering, ejecta, aerodynamic destabilization, and elevated convective heating.

Mission needs to consider, in proposing these solutions, include landers with single and multiple engines, both pulsed and throttled systems, landed masses from 400 to 40,000 kg, and both Lunar and Mars destinations.

Innovations for Vehicle Structures

The development of more efficient lander structures and components are sought to improve the mass efficiency of in-space stages and landers. This may include the adoption and utilization of advanced lightweight materials, especially as used in combination with advanced manufacturing to enable reliable, conformal, and lightweight design innovations.  Of interest are systems for actively alleviating flight loads and environments, reduce integration complexity, or improve system life, enable reusable landing systems, allow restowage and redeployment of solar arrays for multiple mission usage, and develop mechanisms and couplings for continuous use in the lunar dust environment.  Approaches for achieving multifunctional components, repurposing structure for post-flight mission needs, and incorporating design features that reduce operating complexity are also of interest.

Lunar Dust Mitigation

Lunar dust, as experienced during the Apollo program, can have a wide range of deleterious effects on lander subsystems and the people using them. As we head back to the moon with robotic and human landers, the need for effective prevention and/or mitigation measures is needed to ensure long term, nominal operation of lander and surface systems and mission operations. Numerous studies have been performed to characterize dust deposition and potential impacts. Proposals are sought that build on previous studies to better characterize the deposition and impact of dust (see Z13.02 - Dust Tolerant Mechanisms). 

NASA has plans to purchase services for delivery of payloads to the Moon through the Commercial Lunar Payload Services (CLPS) contract. Under this subtopic, proposals may include efforts to develop payloads for flight demonstration of relevant technologies in the lunar environment. The CLPS payload accommodations will vary depending on the particular service provider and mission characteristics. Additional information on the CLPS program and providers can be found at this link: https://www.nasa.gov/content/commercial-lunar-payload-services [25]. CLPS missions will typically carry multiple payloads for multiple customers. Smaller, simpler, and more self-sufficient payloads are more easily accommodated and would be more likely to be considered for a NASA-sponsored flight opportunity. Commercial payload delivery services may begin as early as 2020 and flight opportunities are expected to continue well into the future.  In future years it is expected that larger and more complex payloads will be accommodated. Selection for award under this solicitation will not guarantee selection for a lunar flight opportunity.

References

Lander Technologies: https://www.nasa.gov/content/lander-technologies [307]

Metzger, Philip, et al. "ISRU implications for lunar and martian plume effects." 47th AIAA Aerospace Sciences Meeting including The New Horizons Forum and Aerospace Exposition. 2009.

Plemmons, D. H., Mehta, M., Clark, B. C., Kounaves, S. P., Peach, L. L., Renno, N. O., ... & Young, S. M. M. (2008). Effects of the Phoenix Lander descent thruster plume on the Martian surface. Journal of Geophysical Research: Planets, 113(E3).

Mehta, M., Sengupta, A., Renno, N. O., Norman, J. W. V., Huseman, P. G., Gulick, D. S., & Pokora, M. (2013). Thruster plume surface interactions: Applications for spacecraft landings on planetary bodies. AIAA journal, 51(12), 2800-2818.

Vangen, Scott, et al. "International Space Exploration Coordination Group Assessment of Technology Gaps for Dust Mitigation for the Global Exploration Roadmap." AIAA SPACE 2016. 2016. 5423.

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis, Hardware, Software, Research

Desired Deliverables Description

Deliverables of all types can be infused into the prospect missions due to early design maturity.

State of the Art and Critical Gaps

The characteristics and behavior of airborne particles during descent is important for designing descent sensor systems that will be effective. Furthermore, although the physics of the atmosphere and the characteristics of the regolith are different for the Moon, the capability to model plume/surface interactions on the Moon will feed forward to Mars, where it is critical for human exploration.

Currently, flight data are collected from early planetary landing, and those data are fed into developmental tools, for validation purposes. The validation data set, as well as the expertise, grows as a result of each mission, and is shared across and applied to all other missions. We gain an understanding of how various parameters, including different types of surfaces, lead to different cratering effects and plume behaviors. The information helps NASA and industry make lander design and operations decisions. Ground testing (“unit tests”) is used early in the development of the capability, to provide data for tool validation.

The current post-landing analysis of planetary landers (on Mars) is performed in a cursory manner with only partially empirically-validated tools, because there has been no dedicated fundamental research investment in this area. Flight test data does not exist, in the environments of interest.

Relevance / Science Traceability

Current and future lander architectures such as:

• Artemis
• Commercial robotic lunar landers
• Planetary mission landers

Scope Title

3D Weaving Diagnostics for Validation of Uniform Weaving Processes

Scope Description

NASA is utilizing 3D woven materials to develop Woven Thermal Protection Systems (W-TPS). Examples of recent 3D woven Thermal Protection Systems (TPS) projects include: 3D Multifunctional Ablative TPS (3D-MAT) for compression pads on Orion, Adaptive Deployable Entry Placement Technology (ADEPT) looking at a mechanically deployable aeroshell (similar to an umbrella) that utilizes 3D woven carbon fabric between the ribs, and Heatshield for Extreme Entry Environment Technology (HEEET), containing dual-layer 3D weaves to provide mass efficient TPS solutions for extreme entry environment missions such as to Venus, Saturn and the outer planets. The specialized equipment used to weave 3D woven preforms is based on standard textile equipment that is substantially modified to allow hundreds of layers to be interwoven together. As these complex woven structures are scaled up, it is critical to understand the dynamics of the 3D weaving equipment/hardware and how interactions between different components affect the unit cell of the woven structure and ultimately the material properties.

This subtopic area solicits innovative technology solutions applicable to 3-D woven materials. Specific technology development areas include:

1. Advancements in the understanding of the impact of weaving parameters on the properties of the final weave itself. Looking at developing methods to associate measured weave diagnostics (such as warp tension and beat up force) to understand the effects of woven material parameters (such as fiber volume fraction and yarn crimp), to develop tools to predict the impacts of changes in weaving parameters on final material properties (such as stiffness and strength).
2. Understand what damage may be introduced into the yarns during the weaving operation and the impact of that damage on material performance (such as strength). Objective is to further improve the understanding of how/if key aspects/parameters in the weaving operation (warp tension, beat up force, warp or fill yarns per inch) lead to damage of the yarns and develop methods to reduce weaving damage and/or guidelines to reduce the level of damage induced in the yarns.

References

More info for 3D-MAT, ADEPT, HEEET can be found at: https://gameon.nasa.gov/publications/ [309]

Expected TRL or TRL range at completion of the project: 3 to 6

Desired Deliverables of Phase II

Prototype, Analysis

Desired Deliverables Description

Phase I: Assessment study of potential diagnostic techniques
Phase II: Prototype instrument demonstration on a weaving machine demonstrating increased control capability

State of the Art and Critical Gaps

NASA is investing in woven thermal protection systems, both rigid and mechanically deployable, which both come from a 3D weave. The mechanical/structural properties of these weaves are a strong function of nuances in the resultant weave microstructure; nuances such as fiber volume fraction and the level of crimp in warp versus weft direction or damage induced in the yarns during weaving. An enhanced understanding of the effects of the weaving operation parameters on the final weave itself would better enable scale-up of weaving processes (thickness and width) and tailoring of weaves to meet specific mission needs (how does a change in warp tension to reduce fiber volume fraction manifest itself in changes to crimp or other parameters). There is also value in understanding if/where the weaving operation induces damage into the yarn and its impact on material properties. The current state of the art is very empirical for understanding the effects of weaving parameters on material performance/damage. For example, it is recognized that increasing crimp can decrease stiffness in a material, but there are not good tools to predict the impacts of changes in weave parameters (such as warp tension) are on the crimp level in a weave and how that will impact the properties of the final material. This makes it difficult to predict the impacts of changes in weave on properties and understand how sensitive the relationships are. The end result is that this lack of knowledge limits the flexibility end users have, and requires substantial amounts of testing to understand if a given change is important or not. 

Relevance / Science Traceability

Several potential future missions, outlined in decadal surveys, crewed exploration mission studies, and other supporting analyses, have Entry and Descent (ED)/ Entry, Descent and Landing (EDL) architectures: Mars sample return, high speed crewed return, high mass Mars landers, Venus and gas/ice giant probes. With few exceptions, entry vehicle TPS (Thermal Protection System) for these missions will be composed of materials currently under development and without certification heritage.

NASA planetary exploration programs supporting ED/EDL missions are the intended beneficiaries of this subtopic.