Partially independent control scheme for spacecraft rendezvous in near-circular orbits

Due to the complexity and inconstancy of the space environment, accurate mathematical models for spacecraft rendezvous are difficult to retrieve, which consequently complicates the control tasks. In this paper, a linearized time-varying plant model with consideration of the external perturbations is developed to approximate the spacecraft rendezvous in near-circular orbits. In order to achieve the robust stability with optimal performance cost, a partially independent control scheme is proposed, which consists of a robust anti-windup controller for the in-plane motion and a H _∞ controller for the out-of-plane motion. The effectiveness and advantages of the partially independent control scheme are verified by comparing with other control schemes in a numerical example.