空间站机械臂末端执行器抓取试验技术研究

Research on Grabbing Test of Robotic Arm’s End Effector in China Space Station

末端执行器安装在空间站机械臂的首尾,是机械臂执行空间任务的核心产品。针对地面难以模拟空间零重力下机械臂末端抓取目标过程的问题,通过对空间抓取机构地面验证系统研究,结合中国空间站机械臂末端执行器地面验证需求,提出了半物理试验验证方案,研制了一套基于Steward并联机构的六自由度半物理验证试验系统。完成了末端执行器捕获容差、抓取质量等性能指标的验证,实现了多工况、复杂边界、大负载、大容差等条件下空间机械臂末端抓取功能性能的地面验证。测试结果显示:末端执行器捕获位置容差不小于100 mm,姿态容差不小于10°,抓取目标质量不小于25 t。结果表明末端执行器捕获容差、抓取目标质量等指标均满足要求,并通过了在轨飞行验证。

The end effector is installed at the head and tail of the robotic arm and it is the core equipment for the robotic arm to perform space missions.The process of grasping the target by the end effector in microgravity is difficult to simulated on the ground.To solve this problem,the ground verification system for the space grasping mechanism was studied and a semi-physical test verification scheme was proposed considering the ground verification requirements of the robotic arm’s end effector in China space station.A set of 6-DOF semi-physical verification test system based on Steward parallel mechanism was developed.The verification of performance indicators such as the capture tolerance and grasping target mass of the end effector was conducted and the ground verification of the performance of the space manipulator end grasping function under multiple working conditions,complex boundaries,large loads,and large tolerances were realized.The test results showed that the capture position tolerance of the end effector was not less than 100 mm,the attitude tolerance was not less than 10°,and the grasping target mass was not less than 25 t.The verification results showed that the end effector capture tolerance and the grabbing targe quality could meet the requirements and passed the flight verification in orbit.