A new approach to autonomous rendezvous for spacecraft with limited impulsive thrust: Based on switching control strategy

Abstract

This paper proposes a novel impulsive control approach for autonomous rendezvous of spacecraft with limited thrust. Based on the dynamic model established by Clohessy–Wiltshire (C–W) equations, the rendezvous process is regarded as impulse phase and free motion phase which are considered as closed-loop system and open-loop system respectively. The durations of the two phases are scaled by sampling period. Then, based on Lyapunov theory, two virtual energy functions of the subsystems are introduced, and the rendezvous problem is regarded as an asymptotic stabilization problem of the switching system. Meanwhile, the thrust limitation is also taken into consideration. The impulsive closed-loop control problem is finally transformed into a convex optimization problem and the calculation steps are proposed. With the designed controller, the impulsive thrust during the rendezvous is calculated at the impulse instants. Furthermore, the calculated thrust is kept below a given bound, which can also be minimized according to specific requirements. The effectiveness of the proposed approach is illustrated by simulation examples.