自由漂浮柔性空间机械臂抗扰控制

Anti-disturbance control of free floating flexible space manipulator

自由漂浮柔性空间机械臂的基座不受控,在外太空环境中不仅会受到如关节处摩擦力矩等匹配干扰的影响,还会受到如太阳辐射等非匹配干扰的影响。为了保证柔性空间机械臂系统的稳定及末端轨迹跟踪的精准,对其抗干扰控制方法进行研究。基于奇异摄动法,将柔性空间机械臂系统解耦为刚性与柔性子系统,将非匹配干扰转化为匹配干扰,以便在控制通道对其进行补偿。对分解后的两个子系统,分别设计了带有干扰补偿的计算力矩控制器和滑模控制器,分别实现末端轨迹跟踪和柔性模态快速镇定。通过仿真验证了所提控制方法的有效性。

In the outer space,free floating flexible space manipulator system is not only affected by matched disturbance like friction torque at the joint,but also by mismatched disturbance such as solar radiation.In order to ensure the accurate tracking of end point trajectory and the stability of flexible space manipulator,an anti-disturbance control scheme is studied in this paper.Based on the singular perturbation method,the flexible space manipulator system is decomposed into rigid subsystem and flexible subsystem,and the mismatched disturbance is converted to matched form which can be directly compensated in the control channel.A computed torque controller with disturbance compensation and a sliding mode controller are designed for the two subsystems respectively to carry out end point trajectory tracking and flexible modes stabilization.The simulation results show the effectiveness of the proposed control scheme.