非合作目标捕获过程中姿态反演滑模控制

Attitude Stabilization Backstepping Sliding Model Control in Non-cooperative Target Capturing Process

针对航天器在轨捕获非合作目标过程中姿态快速稳定要求,结合反演和滑模控制的优势,设计了一种鲁棒姿态控制器。分析了抓捕航天器的转动惯量变化特性。基于反演法,先设计了基于姿态跟踪误差的状态反馈器作为虚拟角速度,以保证航天器姿态角快速稳定;设计了使角速度跟踪虚拟角速度的滑模控制器,以提高系统对转动惯量扰动和外部干扰的鲁棒性。最后理论证明该控制器能使闭环系统渐近稳定。针对每个采样点随机产生有界摄动的强不确定性仿真环境,仿真验证了该控制器的快速稳定性和强鲁棒性。

A robust attitude controller has been designed for the rigid body spacecraft to satisfy the demand of rapid attitude stability with bound external disturbance and rotational inertia perturbance. The changing characters of the rotational inertia in the process of spacecraft capturing non-cooperative target is analyzed. A state feedback controller is designed for the kinetics equation, to ensure the attitude angle stabilize quickly. Then,a sliding mode controller is designed for the dynamics equation, to offset the strong external torque disturbance and system parameter perturbance. Finally, theoretical analysis certifies that the closed-loop system is global asymptotic stable under the robust controller. Under the strong uncertain simulation environment, in which, each sample point will produce a bounded random perturbance, simulations verify the controller performance of speedability, strong robustness and low energy.