Adaptive Fault-Tolerant Control of Spacecraft Attitude Dynamics with Actuator Failures

An actuator fault-tolerant attitude control was reported. Two kinds of spacecraft actuator failures were considered, a gain fault, and a deviation fault. An adaptive fault-tolerant control method was proposed for the spacecraft experiencing these actuator failures. The fault-tolerant control relies on an ideal reference model to identify when a fault occurs. The control tracks the ideal reference model to replicate it as closely as possible. This control employs adaptive parameters to improve the responsiveness of the angular velocity error and the quaternion error due to actuator faults. Moreover, the angular velocity error magnitude is more sensitive than the quaternion error to an actuator fault. This adaptive control has been shown to significantly improve the performance over a conventional control in the presence of these actuator faults.