Attitude and Orbit Coupled Control for Spacecraft Rendezvous and Docking Considering Safe Constraint

Abstract

This paper studies attitude and orbit coupled control scheme for spacecraft rendezvous and docking. On basis of the spacecraft attitude and orbit coupled model using modified Rodrigues parameters (MPRs) on the chaser spacecraft body coordinate system, an adaptive sliding mode controller is proposed for the situation of unknown upper bound of external disturbances. A new artificial potential function is presented to approximate final approaching corridor. The use of the potential function in the controller can guarantee the chaser move in the safe area. Lyapunov theory is adopted to prove that the states of the system under the proposed controller are bounded, and the chaser can realize rendezvous and docking without collision. The numerical simulations are conducted to further demonstrate the effectiveness of the proposed controller.