Backstepping based adaptive sliding mode control for spacecraft attitude maneuvers

This paper aims to address the attitude control problem of a rigid spacecraft involving parameter variation and external disturbance. A backstepping based adaptive sliding mode control (B-ASMC) strategy is proposed as a solution, where the upper bounds of the parametric uncertainty and disturbance are not required for the controller design. Compared to current adaptive sliding mode control (ASMC) design, the proposed B-ASMC design has two advantages. First, unlike existing ASMC algorithms, where only the asymptotical stability of the sliding function is achieved, this paper shows that the asymptotical stability of the attitude states, i.e., the attitude parameter and the angular velocity, can be guaranteed by B-ASMC. Second, the system performance is improved due to two additional terms obtained in the backstepping framework. Detailed design principle and rigorous stability analysis are provided. Finally, a large angle Move-to-Rest attitude maneuver is employed in the numerical simulation to verify the effectiveness of the proposed strategy.