Observer-based nonlinear stabilization control design for flexible satellite attitude system

In this paper, an observer-based nonlinear stabilization control method is presented for the problem of flexible satellite attitude maneuver and vibration suppression. By introducing the auxiliary variables, the attitude mode of flexible satellite is converted into the corresponding nonlinear polynomial state space description. According to the structural features of attitude system, the nonlinear state feedback controller based on the reduced-order observer is obtained by using the Lyapunov theory and polynomial sum of squares (SOS) method. Finally, the proposed approach is applied to the attitude control of a flexible satellite and the simulation results show that both the fast rotational maneuver and the vibration suppression are well realized.