基于光学定位系统反馈的机器人末端位姿误差在线补偿方法

Online Compensation Method of Robot End-effector Pose Error Based on Optical Tracking System

为了提高手术辅助机器人的定位精度,提出了一种基于改进L-M迭代的机器人末端工具位姿误差在线补偿方法。该方法无须标定机器人运动学模型参数,将机器人的几何误差、非几何误差和坐标系配准误差都归结于机器人关节误差,利用光学定位系统反馈机器人末端工具位姿,通过雅可比矩阵把机器人末端工具位姿误差映射到机器人关节空间,迭代改变机器人关节位置,使机器人末端工具位姿逐渐逼近目标位姿。实验结果表明,所提方法可将机器人末端工具位置误差降至0.1mm,末端工具姿态误差降至0.05°,显著提高了机器人末端工具位姿精度。

In order to improve the pose accuracy of surgical robot,an online compensation method of robot end-effector pose error based on improved L-M iteration method is proposed.The robot kinematic model parameters doesn′t need to be calibrated.The geometric error and non-geometric error of the robot and the coordinate system registration error are attributed to the robot joint error.An optical tracking system is used to measure the robot end-effector pose.The end-effector pose error is mapped to the joint space through the Jacobi matrix and the joint positions are changed through multiple iterations,making the robot end-effector pose gradually approaches the target pose.The experimental results show that the method can reduce the positioning error of the robot end-effector less than 0.1mm and the orientation error less than 0.05°,which significantly improves the end-effector pose accuracy of the robot.