SpiderFab空间机械臂系统耦合动力学计算与仿真

摘要

The SpiderFab-type space manipulator is a typical space-based robot system.In order to quantitatively understand the influence on its floating base,which is caused by the motion of a manipulator,and to design its position and orientation control system,kinematics and dynamics equations are built.The coupling dynamics between a floating base and a manipulator is presented based on the conservation law of momentum.It is illustrated that the state change in the floating base is not only dependent on the current manipulator joint velocities but also joint paths.To deeply elaborate the coupled dynamics,three computer simulations of a space-based 3-degree-of-freedom (DOF) manipulator system are conducted.Three joint velocity inputs are given,and the post variation of the floating base is to be computed.The correctness of the method is demonstrated.%SpiderFab型空间机械臂是一种典型的漂浮基空间机械臂系统.为了定量的认识机械臂在运动过程中对基体的扰动影响,并以此为依据设计浮动基体的位姿控制系统,建立了系统的运动学、动力学方程.根据系统动量守恒条件显式的表达出基体与机械臂之间的速度耦合关系,并由此说明基体的位姿变化不仅与机械臂实时关节速度有关,还与机械臂的历史关节路径有关.为了更进一步说明系统内存在的动力学耦合问题,针对一个漂浮基三自由度空间机械臂系统,设计了三组仿真试验.三组不同的关节速度曲线作为输入条件,求解基体关节所受的扰动量.仿真结果证明了计算方法的正确性.