空间机械臂捕获卫星过程的碰撞动力学模拟及镇定运动的鲁棒控制

摘要

The impact dynamics and post-impact control for stabilizing of a free-floating space manipulator capturing an unknown motion satellite are studied .The dynamical models of the space manipulator and satellite are separately derived from second Lagrange equation and New ton-Euler equation ;the impact effect is calculated base on kinematics and impact force transmission relationship ;after the satellite cap-turing ,by combining the above dynamics models of space manipulator and satellite ,the post-impact dynamics model of the combinational system is presented ;and then an augmented robust control algo-rithm is designed for stabilizing the motion of the post-impact combinational system .This control can be employed under the space manipulator base’s position uncontrolled ,and the control equation still keep linear for the uncertain satellite parameters .Finally ,the simulation results show the system motion state of the capture process ,and verify the validity of the above robust control for stabilizing .%讨论了漂浮基空间机械臂捕获未知运动目标卫星的接触碰撞动力学建模和接触碰撞后系统镇定运动的控制问题。利用第二类拉格朗日方法和牛顿-欧拉法分别建立了接触碰撞前漂浮基空间机械臂和目标卫星两分体系统的动力学模型；以此为基础借助于空间机械臂与目标卫星接触点间的运动几何关系、力传递关系，计算了接触碰撞所产生的影响效应；捕获卫星后，联立空间机械臂与卫星接触碰撞前的动力学模型，建立了接触碰撞后两系统组合体动力学模型；并设计了增广鲁棒控制算法，以对受碰撞冲击后处于不稳定的组合体系统进行镇定运动控制。上述控制方法能应用于空间机械臂载体位置不受控情况，并能使组合体系统控制方程关于卫星不确定参数呈线性化关系。最后，利用数值仿真模拟捕获过程系统运动状态，验证了上述鲁棒控制镇定运动的效果。