NASA SBIR 2008 Solicitation


PROPOSAL NUMBER: 08-1 X13.01-9762
SUBTOPIC TITLE: Active Charged Particle and Neutron Radiation Measurement Technologies
PROPOSAL TITLE: TEPC Microdosimeter for LEO and Beyond

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
LVI Systems Inc.
1331 Broadview Road
West Richland, WA 99353 - 5207
(206) 600-2990

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Thomas J. Conroy
1331 Broadview Road
West Richland, WA 99353 - 5207
(509) 430-5604

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

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
A new generation of Tissue Equivalent Proportional Counters (TEPCs) for micro-dosimetric measurements will be designed, incorporating recent advances in the electronics industry and a new detector configuration. The unit is projected to be 2.5x4.5x1 in, weigh less than 8 oz, and consume less than 100 mW of power.

A detector configuration of thirteen half-inch spheres arranged in a 2-D array will be used - twelve connected together to form an equivalent spherical 1.74-inch diameter detector for measuring low fluence environments, and the thirteenth detector connected independently allowing measurements during high fluence periods when the larger detector would saturate (such as during solar particle events).

The new electronics will continuously convert the detector data at 1 Mhz. Digital methods will allow both the setting of any threshold and the determination of event peaks, and allow more sophisticated signal processing to be used to reduce noise and eliminate micro-phonics. In addition, a bi-processing method of analyzing the detector signals will allow determination of dose by both integration method and peak method which can then be analyzed to provide accurate total dose readings for the events from the threshold to below 0.05 keV/micron. The spectra below several kev/micron is important as it can contain up to 40% of the total dose.

The detector filled with pure propane will simulate a 2 micron site size. Two spectra will be stored each minute, and total integrated dose, dose above threshold, dose equivalent dead-time will be provided every second. The spectra will have 2048 channels at 1 keV/micron for each channel, to a maximum of 2047 keV/micron. The threshold for peak detection and analysis can be set anywhere from 0.4 to 20 keV/micron. The unit will be capable of measurement ranging from less than 100 nGy/hr to over 100 mGy/hr.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
Accurate monitoring of radiation exposure levels are required in order to access health risks, and to help limit exposures levels to an acceptable risk. Tissue Equivalent Proportional Counters (TEPC) have been used as a critical part of these measurements on the Space Shuttle and on the International Space Station (ISS) for many years. The current design has a number of technical limitations which should be improved for future missions, as well as the size and power consumption being reduced by updating the design with modern smaller, lower power electronics. The smaller, lower power, more capable TEPCs would satisfy the requirements of the upcoming Exploration class missions, and other human activities in space. This new TEPC design, or variants of it, will allow more extensive monitoring, not only in existing habitats such as ISS, but also in future habitats in space as well as on the moon and potentially Mars.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The miniaturized TEPC being proposed would be valuable to several mainstream industries. The nuclear industry and the commercial launch vehicle industry would both have a need for this type of personal radiation monitoring. Also, monitoring the radiation environment on high-flying military and commercial aircraft could be done with this smaller less expensive unit that currently available HAWK unit. The accelerator industry, as well as all other industries that have regulatory requirements for radiation monitoring (especially neutron radiation and mixed fields), would be potential applications for this new TEPC.

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.

Particle and Fields
Pilot Support Systems
Portable Data Acquisition or Analysis Tools
Radiation Shielding Materials
Spaceport Infrastructure and Safety

Form Generated on 11-24-08 11:56