柔性机械臂辅助空间站舱段对接阻抗控制

空间机械臂辅助舱段对接过程中存在测量与控制误差,易导致对接机构间存在较大接触力,传统FMA (Force MomentAccommodation)控制方法在测量接触力时无法消除大负载惯性力对测量的影响,且测量仪器的引入会进一步降低空间柔性机械臂的刚度。为此,文章提出了柔性机械臂辅助大负载空间舱段对接的阻抗控制方法,采用拉格朗日法推导了空间机械臂的关节输入力矩方程作为前馈输入,建立了含动力学前馈的空间机械臂阻抗控制程序,并以在商业软件ADAMS中建立的空间柔性机械臂与对接舱段组成的系统动力学模型作为控制对象,对系统进行ADAMS灢Matlab联合仿真。仿真结果表明,按照此控制方法,系统可克服外力干扰使目标解析点按照期望的方式运动;同时,通过测量机械臂关节运动参数即可实现对外力的准确感知,而不需额外添加力传感器,既消除了大负载惯性力对测量的影响,也不会导致柔性机械臂刚度的降低。

Impedance Control of Space Flexible Manipulator System Assisted Docking of Space Station

Control and measurement errors could lead to great contact forces during the space flexible manipulator assisted spacecraft docking.Theforce sensor could not get rid of the inertia force and it would make the manipulator more flexible.To solve these problems,a dynamic model of space manipulator was established as the feed forward input of the joints torque.The impedance control scheme was established,and a dynamic model of a system consisted of a space manipulator and a space station was built by the software of ADAMS. The co-simulation was done by the software of Matlab and ADAMS.The results show that the space manipulator system works correctly even through the interfering forces during the simulation.The space manipulator system also operates correctly in the docking direction,and is free in the other directions so that it can adapt to thes pace manipulator system assisted spacecraft docking.Atthesametime,thesystem canovercometheinfluenceofthebigload of the space station to the force measurement by measuring the joints parameters.While,it will not make the space manipulator more flexible.