Attitude stabilization of flexible satellite subject to external disturbance and actuator constraint

This work presents a nonlinear control approach to address the problem of attitude stabilization for flexible satellite. Actuator constraint and unknown external disturbance are explicitly considered. Firstly, a backstepping based control law is proposed in the absence of actuator constraint. It guarantees that the attitude and the angular velocity are asymptotic stable even in the presence of unknown appendage´s vibration and disturbance. Take actuator constraint into account, another backstepping based controller is then developed. It shows that the closed-loop attitude system is uniformly ultimately bounded. Simulation results are also presented to demonstrate the effectiveness of the proposed scheme.