TRAJECTORY PLANNING AND HIERARCHICAL SLIDING-MODE CONTROL OF UNDERACTUATED SPACE ROBOTIC SYSTEM

This article addresses the trajectory tracking control problem of the underactuated space robotic system (UASRS), in the case that one or several joint drivers do not work. Firstly, the kinematic and dynamic models of the free-floating UASRS are established. Subsequently, the optimal trajectories are obtained utilizing the sinusoidal polynomial function and the particle swarm optimization algorithm (PSO). Then, a hierarchical control strategy based on sliding mode control is proposed in ideal conditions. Furthermore, this article introduces the backstepping adaptive control strategy to design a hierarchical backstepping adaptive sliding mode controller under external disturbance, which has stability by detailed proof. Finally, the numerical simulations are carried out and the results verify the effectiveness of the proposed control method.