Fault detection and isolation in the NT-OMS/RCS

Abstract

In this paper, we consider the problem of test design for real-time fault detection and diagnosis in the Space Shuttle's non-toxic orbital maneuvering system and reaction control system (NT-OMS/RCS). For demonstration purposes, we restrict our attention to the shaft section of the NT-OMS/RCS, which consists of 160 faults (each fault being either a leakage, blockage, igniter fault, or regulator fault) and 128 sensors. Using the proposed tests, we are able to uniquely isolate a large number of the faults of interest in the NT-OMS/RCS. Those that cannot be uniquely isolated can generally be resolved into small ambiguity groups and then uniquely isolated via manual/automated commands. Simulation of the NT-OMS/RCS under various fault conditions was conducted using the TRICK/sup /spl reg// modeling software.