Integrated relative position and attitude control for spacecraft rendezvous with ISS and finite-time convergence

Abstract

This article is concerned with the relative motion control for spacecraft rendezvous in the presence of external disturbance. First, to ensure accurate relative position tracking and attitude synchronization between a pursuing spacecraft and a target spacecraft, a novel integrated six-degrees of freedom (6-DOF) dynamics model is established with consideration of thrust layout. In particular, based on line of sight coordinate frame, the relative position dynamics is more suitable for actual measurement circumstances and applicable for arbitrary orbital forms. Subsequently, to implement the rendezvous mission, two groups of control schemes are designed using backstepping method with input-to-state stable property and finite-time control technique, respectively. In Lyapunov theoretical framework, the designed controllers are proved to guarantee the convergence of relative position and relative attitude tracking errors. Finally, simulations results are carried out to validate the effectiveness of the proposed control approaches.