SPACECRAFT ENVIRONMENTAL ANOMALIES EXPERT-SYSTEM

An expert system has been developed by The Aerospace Corporation, Spac e and Environment Technology Center for use in the diagnosis of satell ite anomalies caused by the space environment. The expert system is de signed to determine the probable cause of an anomaly from the followin g candidates: surface charging, bulk charging, single-event effects, t otal radiation dose, and space-plasma effects. Such anomalies depend o n the orbit of the satellite, the local plasma and radiation environme nt (which is highly variable), the satellite-exposure time and the ''h ardness'' of the circuits and components in the satellite. The expert system is a rule-based system that uses the Texas Instrument's Persona l Consultant Plus(TM) expert-system shell. The expert-system's knowled ge-base includes about 200 rules, as well as a number of data bases wh ich contain information on spacecraft and their orbits, previous space craft anomalies, and the environment.