Abstract
This thesis describes the development and the testing of an advisory system for a digital autopilot on the Space Shuttle. A simplified spacecraft attitude control simulator has also been developed and tested using real-time telemetry data. The advisory system detects off-nominal behavior of the digital autopilot and issues warning messages. The types of off-nominal behavior considered in this thesis are overshoot, chattering, and unmodeled torque bias. The simulator is a simplified on-orbit reaction control system digital autopilot. It plays an important role in the estimation of the torque bias. It can also be used for predicting the future behavior of the attitude controller. Three example cases are investigated using the advisory system and the simulator. The results show that the advisory system is capable of detecting off-nominal behavior in real-time. The simulator output tracks the actual telemetry data when a torque bias compensation mode is used. In addition, the effects of inconsistent and noisy telemetry data are examined and future actions are recommended.
Bae, Han-Wook (2002). A digital autopilot simulator and advisory system for detecting off-nominal behavior. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -2002 -THESIS -B34.