Model Based Autonomy - How Model without Human Expertise Can Facilitate Fault Diagnosis and Other Spacecraft Tasks ? -

A model based fault diagnosis system for satellites is proposed which autonomously infers the cause of failure from telemetry-type time history data using functional models of satellite subsystems. The key research issue is how and to what extent a model without human expertise can solve the fault diagnosis problem. The evaluation results of the prototype system indicate that though non-deterministic search process guided by some weak logic can solve the problem within practical time to some extent, it still has severe limitations coming from the lack of capability to measure the similarity of two telemetry data. Extraction and utilization of attributes useful for diagnosis task is a promising approach, and one method is proposed for autonomously defining such important attributes from telemetry data.