NASA SBIR 2007 Solicitation


PROPOSAL NUMBER: 07-1 S4.07-9076
SUBTOPIC TITLE: Mini-Micro Thrusters, LOX / Hydrocarbon Propulsion, and Attitude Control Systems
PROPOSAL TITLE: Pulsed Electrogasdynamic Thruster for Attitude Control and Orbit Maneuver

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
Physical Sciences, Inc.
20 New England Business Center
Andover, MA 01810 - 1077
(978) 689-0003

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Takashi Nakamura
20 New England Business Center
Andover, MA 01810 - 1077
(925) 743-1110

Expected Technology Readiness Level (TRL) upon completion of contract: 4 to 5

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
A new pulsed electric thruster, named "pulsed electrogasdynamic thruster," for attitude control and orbit maneuver is proposed. In this thruster, propellant gas is introduced into the thrust nozzle through a fast acting gas valve. When the propellant gas partially fills the thruster nozzle in 100~200 microsecond, a short, high voltage pulse is applied to break down and heat the propellant gas. The typical duration of the pulsed discharge is 10 microsecond. The heated propellant gas expands through the nozzle generating a high impulse (~mN-s per pulse) at a high specific thrust (120 micro N-s/joule). The specific impulse (Isp) will be in the range of 1000~1400 sec. This process can be repeated at a frequency which satisfies the spacecraft thrust requirement. The thrust generating mechanism of the proposed thruster is gasdynamic expansion, not magnetohydrodynamic interaction. The proposed thruster is different from the conventional pulsed electrothermal thruster in that the joule heating of the propellant takes place as the propellant gas expands through the divergent nozzle, thereby eliminating the heat and momentum losses at the nozzle throat. Our objectives are: (i) establish proof of concept; (ii) develop an engineering model; and (iii) develop a proto-flight model of the proposed thruster system.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The Pulsed Electrogasdynamic (PEG) thruster, when developed to technical maturity, will be used for satellite mobility, such as rapidly changing position for rendezvous, attitude control, orbital maneuver and control satellite constellation formation. These maneuvers require a relatively high thrust (mN ~ N) at a moderately high specific impulse (Isp almost equal to 1000 sec) and a high electric efficiency (~60%). The PEG thruster will meet this requirement in a broad thrust range. For example, when operated at 1 Hz, the PEG thruster will generate a thrust of 1 mN with 10 W of electric power input. At higher pulse rates, 100 Hz for example, 100 mN of thrust will be generated with 1 kW of electric power. Higher thrust can be obtained by scaling up the thruster size. The PEG thruster in a low power mode will also be used for station keeping applications. To this end, a PEG thruster suite can be added to any spacecraft equipped with a N2H4/NTO Monopropellant/Bipropellant propulsion system without incurring a mass penalty for high precision "digital" attitude corrections at a higher Isp than is obtained with the conventional monopropellant solution. Furthermore storable "Green" propellants such as N2O and NH3 are very suitable as PEG thruster propellants. The PEG thruster will serve NASA's Science Mission Directorate needs in earth orbit, near-earth and in deep space.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The Pulsed Electrogasdynamic (PEG) thruster will be very useful for military applications that require: (i) wide dynamic range in thrust; (ii) high Isp; and (iii) high electrical efficiency. For purely commercial applications, the PEG thruster will be useful for satellite station keeping, orbit raising, and attitude control. For such applications the following advantages of the PEG thruster can be fully exploited: (i) various kinds of propellant gas can be used; (ii) thrust level can be adjusted by changing pulse frequency over 2~3 orders of magnitude; (iii) the life time of the thruster hardware will be much longer than the other thrusters; and (iv) construction of the thruster is simple and can be scaled easily.

NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.

Micro Thrusters

Form Generated on 09-18-07 17:50