为削弱在轨加注过程中主被动端碰撞冲击对空间机器人的影响，提出了基于力／位混合的柔顺控制律。首先通过第二类拉格朗日方程建立了漂浮基座空间机器人一般运动学模型和考虑环境接触的动力学模型。其次，设计了“杆‐锥式”加注主被动端装置，根据主被动端的接触特点，建立了点面接触的碰撞动力学模型，并给出相应的碰撞力计算方法。接着，将加注对接问题转化为以基座为参考系的末端运动控制问题，得到了机械臂关节期望运动规律，进而设计了位置环控制律；根据加注主被动端的位置关系计算得到碰撞力，进而设计了力／力矩环控制律，结合顺应选择矩阵最终得到力／位混合控制器，以减小杆锥对接时碰撞对空间机器人基座及末端的冲击影响。最后，仿真结果表明，对接方向的位置误差由初始值降至零，对接过程碰撞产生的力不超过10 N ，满足末端工具冲击承载。各关节角度变化平缓，关节力矩不超过13 N m ，满足机械臂关节力矩最小承载，所设计的控制器使得加注主被动端完成柔顺对接。%Force/position hybrid compliant control law was proposed to weaken the effect on space manipulator when an active device was involved in a collision with a passive device . Firstly , using the second kind of Lagrange equations , the floating base space manipulator kinematics and dynamics model were constructed considering the contact environment . Secondly ,a pole‐cone type refueling device was given .According to the contact characteristics of the active and passive device , a point‐surface contact collision dynamics model was established , and the corresponding collision force calculation method was given . Then , refueling docking problem was formulated for spacecraft‐referenced end‐point motion control problem . On this basis , the desired manipulator end‐point trajectory was planned and the position loop control law was proposed . The collision force was obtained according to the position between the refueling active and passive devices ,and the force/torque loop control law was proposed . Furthermore , combined with adaptation selection matrix , the force/position hybrid controller was obtained to reduce the collision impact on space robot . Finally , simulation results show that the docking direction position error reduces to zero from the initial value , and the collision force is less than 10 N during docking , and joint torque does not exceed 13 Nm . The active and passive devices complete compliant contract by the designed force/position hybrid controller .
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