|
|
|
- Fault Tolerant Satellite Systems: SoHaR is developing
operating system extensions to enable adaptive fault tolerance
to be applied in real time satellite control. This demanding
environment must account for changes in both mission requires
(e.g., when to optimize power consumption vs. recovery time)
and the failure and recovery characteristics of the individual
system.
- Fault Tolerant Robotics for Spaceborne Applications: Under
contract to the NASA Jet Propulsion Laboratory, SoHaR has
developed software techniques to implement fault tolerance
in robots used for applications such as the Space Station.
- Spaceborne Failure Data Analysis: Under contract to the
NASA Langley Research Center, SoHaR investigated failure
data from major NASA programs in order to assess overall
trends, identify strengths and weaknesses, and make recommendations
for design, qualification, and analysis requirements in
future NASA programs for increasing mission reliability.
- Fault Tolerant Software Development: As part of research
to support the Strategic Defense Initiative (SDI), SoHaR
conducted two separate efforts to demonstrate and apply
a methodology for producing fault tolerant software for
spaceborne applications.
- Reliability Modelling for Spacecraft: Under a subcontract
in support of SDI, SoHaR developed a reliability model which
includes sparing and can be integrated into a Fleet Effectiveness
model.
- Spaceborne Electronic Component Reliability Prediction:
Under contract to the U.S. Air Force Rome Air Development
Center (RADC), SoHaR demonstrated that in most cases a decreasing
hazard model is more appropriate for space applications
than the conventional constant hazard one. The work, which
resulted in several articles and technical reports, also
proposed procedures which were incorporated into MIL-HDBK-217E
for spaceborne electronics.
- Design Concepts for Reliable Spaceborne Mini- and Microcomputers:
SoHaR assisted a major aerospace contractor in the development
of design concepts for a new line of spacecraft computers
that emphasize fault tolerance and self-test.
- Analysis of Flight Control Software Faults: Under several
contracts with NASA centers, SoHaR analyzed fault data from
the Space Shuttle and a number of flight control development
efforts. Results of the analysis are used to arrive at meaningful
fault classifications and to formulate "lessons learned"
for future development efforts.
- Software Failure Analysis: Under a subcontract to the
Jet Propulsion Laboratory, SoHaR conducted an analysis and
classification of software failures on a major satellite
data communication system including classification of the
probable cause of the failure and the program phase in which
the fault occurred.
- Fault-Tolerant Spaceborne Computer: SoHaR supported the
U.S. Air Force in their efforts to develop a general purpose
fault tolerant spaceborne computer. Specific SoHaR tasks
in this multi-year project were Element Reliability Assessment,
Fault Tolerance Evaluation, Review of Specification Compliance,
and Evaluation of User Reliability Requirements.
|
|
|
