基于反步法的主从航天器相对姿态控制

对主从航天器的相对姿态控制问题,考虑从航天器系统不确定因素,提出了一种基于反步法的姿态控制方法,并引入自适应控制律.该方法首先根据主从航天器的相对位置信息,解算出从航天器观测轴指向主航天器以及从航天器跟踪主航天器轨道坐标系等两种任务的期望姿态;然后基于修正罗德里格参数(MI(P)描述的从航天器姿态误差动力学模型设计了姿态控制器以及针对航天器惯量的不确定性设计了自适应控制律;并基于Lyapunov方法从理论上证明了该方法能够实现全局渐近稳定的相对姿态控制.最后将该方法应用于某编队飞行任务,仿真结果表明此控制器能够实现其编队飞行控制,具有良好的控制性能.

Backstepping-based relative-attitude control for the leader-follower spacecrafts

An attitude-control scheme based on the backstepping technique is developed for controlling the relative attitude between the leader spacecraft and the follower spacecraft, and the adaptive control law is applied to deal with the uncertainties in the follower spacecraft attitude system. According to the current relative positions between the leader and the follower, this scheme determines the required attitude of the follower to align its observation axis to the leader, and the required attitude of the follower to track the orbital coordinates of the leader. With the above-obtained results, an adaptive backstepping attitude controller is synthesized for the follower with unknown inertia matrix, based on the follower attitudeerror dynamic model represented by modified Rodrigues parameters (MRP). Lyapunov stability analysis shows that the developed controller ensures the relative-attitude control system for globally asymptotical stability. Simulation results of the application to a spacecraft formation flying show the effectiveness and feasibility of the designed controller.