Malfunction Detection System for Advanced Spacecraft

A design approach for a Malfunction Detection System (MDS) to beused on board a manned spacecraft is considered. This design is directed toward orbiting laboratory type vehicles, in which man will be subjected to hostile environments for extended periods of time. The prime purpose of the MDS will be to monitor and evaluate critical signals and display out-of-tolerance conditions. This paper initially discusses a mathematical model approach to a monitoring-system design. Another topic covered is the feasibility of using some value less than the specified tolerance as a signal ¿test¿ limit. Finally, various design decisions and trade-offs involved in choosing a monitoring subsystem configuration are discussed, and the conclusion is that the approach is feasible and could be expanded to include other capabilities.