Actuator Fault and Disturbance Observation for Microsatellite Using Only Angular Velocity Information

In order to improve the on-orbit autonomous ability of microsatellites, an actuator fault and disturbance observation method is proposed using only angular velocity information in this paper. The algorithm is motivated by the well-established disturbance observation method of Euler-Lagrange systems. The theoretical deduction indicates that the observation error of the observer is uniformly ultimately bounded (UUB). The proposed method is shown to be suitable for any attitude of microsatellites, and independent of the states of actuators. The observation performance is evaluated by numerical simulations.