Abstract
based advisory system for detecting off-nominal behavior of spacecraft digital autopilots(DAP) in real-time. The DAP of the space shuttle is used as a simulation model for this study. Errors in attitude and attitude rate are determined from the space shuttle dynamic model, and the control torque required, by the phase plane switching logic and jet selection logic. Rules-based methods for detecting off-nominal behavior such as chattering, overshoot, and torque bias are developed. This advisory system can be used either for simulations on the ground or for onboard use by astronauts. It can also accept telemetry data and issue warning messages if significant deviations are observed between simulations and the actual behavior of the DAP.
Jung, Hee (1998). Development of a rules-based advisory system for detecting off-nominal behavior of spacecraft digital autopilots. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1998 -THESIS -J863.