Identifying minor system errors before they become critical is one key to developing safer, more reliable and less expensive space vehicles. As part of NASA's Space Launch Initiative (SLI), Honeywell, Phoenix, and NASA Ames Research Center, located in California's Silicon Valley, recently demonstrated a suite of advanced diagnostic tools known collectively as Integrated Vehicle Health Management (IVHM).

The milestone demonstration showed that separate technologies could be integrated into a cohesive package that can handle realistic problem scenarios that might be encountered in space.

"The Space Launch Initiative develops critical technologies, but it also demonstrates the value of those technologies in a relevant environment. Early demonstrations such as this are part of making sure we are on the right track," said William Kahle, IVHM project manager at NASA Ames.

For the demonstration, realism was a must, so engineers looked at various types of failures. Along with key subsystem failures, cross-subsystem 'sympathetic' failures were tested. 'Sympathetic' failures occur when problems in one system affect the performance in an unrelated system. To handle these types of failures and to build system flexibility, the engineers used a variety of techniques.

"We recognized early on that the health management requirements of RLVs (reusable launch vehicles) demand a range of diagnostic approaches from model-based to expert system technologies," said Ronald Quinn, principal investigator for Honeywell.

To ensure realism, NASA Ames and Honeywell collaborated to develop scenarios and select component technologies that will provide relevant and significant results for the next generation of RLVs.

In one scenario, the IVHM systems were able to determine that an indicated pressure-system failure in a propulsion subsystem actually was caused by a failure in a power system control module.

"This is a realistic scenario that occurs often in complex systems such as RLVs," said Dr. Ann Patterson-Hine of NASA Ames. "It demonstrates the need for a vehicle-wide health management system."

NASA Ames, which leads the IVHM effort for the agency's Space Launch Initiative, also has developed other diagnostic and simulation tools.

Livingstone, a model-based reasoner, was selected to emulate the propulsion health management system while TEAMS (Testability Engineering and Maintenance System), a product of Ames' Small Business Innovative Research program, provided model-based reasoning for the power system and provided vehicle level diagnoses.

Spacecraft Control Language was used to develop expert systems and the architectural infrastructure that integrated these technologies. They cover a wide range of capabilities necessary to satisfy the health management needs for RLVs.

Community
Email This Article
Comment On This Article

Related Links
SpaceTransporation.com
Honeywell
SpaceDaily
Search SpaceDaily
Subscribe To SpaceDaily Express
Rocket Science News at Space-Travel.Com

Memory Foam Mattress Review

SPACE MEDIA NETWORK PROMOTIONS Solar Energy Solutions Tempur-Pedic Mattress Comparison ... Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News