研究了双臂空间机器人系统捕获目标时发生碰撞的冲击效应及之后形成的闭链系统的稳定控制问题.针对具有漂浮基的空间机器人系统及目标系统,分别采用拉格朗日第二类方程及牛顿欧拉法分别建立其动力学模型.在双臂空间机器人捕获目标的过程中,利用力的传递关系及运动几何关系,分析了两者的瞬间碰撞冲击效应.对于两者接触后形成翻滚的联合体系统,结合闭环约束条件及总动量守恒原则,获得了闭链系统动力学方程;并设计了滑模变结构控制方案,以完成镇定运动控制.考虑到空间机器人闭链系统存在控制器冗余的情况,运用最小权值范数法,均衡分配各关节力矩.最后采用数值仿真实验模拟了碰撞冲击效应及镇定过程,并验证了上述控制方案的有效性.%The impact effect of dual-arm space robot capturing a target was analyzed and the stabili-zation control problem after impact was studied. With the Lagrange equation and the Newton-Euler approach, the dynamic models of the space robot system and the target system were established. During target capturing, the instantaneous impact effect of the two systems was analyzed by using the geometric relationship and the force transitive relation. As to the formed unstable complex system, the model of closed-chain system was derived by the principle of momentum conservation and the closed-loop constraints. The variable structure sliding mode control scheme was designed for the closed-chain system to realize stabilization. For the existence of the controller redundancy, the weighted minimum-norm theory was used to distribute the torques evenly to each joint. Numerical simulation was used to simulate the process of the collision impact effect and the stabilization con-trol. The validity of the proposed control scheme was verified.
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