Adaptive relative orbit control for spacecraft nonlinear rendezvous with thrust saturation by using second order anti-windup system

Based on the classical spacecraft nonlinear Hill model, for spacecraft rendezvous to the target on the elliptical orbit, the relative orbit control problem is investigated in consideration of thrust saturation and service spacecraft’s unknown mass. The reference trajectory (RT) generator is applied to construct whole motion trajectory. By utilizing anti-windup (AW) technique and mass estimate law, a comprehensive adaptive relative orbit control method is proposed. Within the Lyapunov framework, the practical stability of tracking error state system related to the relative orbit has been proven theoretically. Compared with existed works, the main contributions are that: 1) This research further considers the thrust saturation and AW technique with a new second-order auxiliary system is constructed; 2) This paper reveals the extra skew-symmetric property in nonlinear Hill model, which simplifies the design of relative orbit control law. Finally, the good performance of proposed control method is verified by spacecraft rendezvous simulations.