面向高精度显微手术机器人的RCM机械臂误差补偿方法  

Error Compensation Method for High Precision Microsurgical Robot with RCM Manipulator

作　　者：白明[1,2] 张明路 张赫[1] 庞淋峻[1] 赵杰 BAI Ming;ZHANG Minglu;ZHANG He;PANG Linjun;ZHAO Jie(Harbin Institute of Technology,State Key Laboratory of Robotics and System,Harbin 150006;School of Mechanical Engineering,Hebei University of Technology,Tianjin 300401)

机构地区：[1]哈尔滨工业大学机器人技术与系统国家重点实验室,150006 [2]河北工业大学机械工程学院,天津300401

出　　处：《机械工程学报》2022年第18期170-180,共11页Journal of Mechanical Engineering

基　　金：国家自然科学基金(52175008,920480301,U1913211,52175008);河北省自然科学基金(F2021202016);省部共建电工装备可靠性与智能化国家重点实验室(河北工业大学)(EERI_0Y2021004);机器人技术与系统国家重点实验室(哈尔滨工业大学)(SKLRS2022KF17)。

摘　　要：为了实现机器人辅助微创手术,带有远程运动中心(Remote central motion, RCM)机构的机械臂被广泛应用于手术机器人系统。操作尤为精细的显微手术对机器人的精准度和安全性提出更高要求。针对眼底显微手术机器人的构型特点,在运动学标定基础上提出一种减小定位误差、RCM约束点偏差和逆运动学求解时间的补偿方法。建立机器人误差模型并辨识几何参数;基于功能和机构特点,建立RCM约束点和末端点的运动学方程和误差补偿模型,采用冗余自由度实时补偿RCM约束点偏差,并以解析解实现RCM约束点偏差和末端位置误差同时补偿的高效逆运动学求解方法;在所搭建的手术机器人平台上进行试验,结果表明,所提出的方法将末端定位误差减小到0.142 6 mm,与迭代法相比RCM约束点偏差减小92.72%,且计算效率提升89.97%,验证了该方法的有效性,对提升显微手术机器人的精准性和安全性具有重要意义。To achieve robot-assisted minimally invasive surgery, manipulator with remote center motion(RCM) mechanism is widely used in surgical robot system. Especially, microsurgery with particularly precise operation requires higher precision and safety of the robot. Aiming at the characteristics of fundus microsurgery robot, based on kinematic calibration, an error compensation method is proposed to reduce positioning error, RCM bias and inverse kinematics solution time. The error model of the robot is established and the geometric parameters are identified;Based on the function and characteristics of the mechanism, the kinematic equations and error compensation model between RCM and end-effector points are established, redundant degrees of freedom are used to compensate the RCM bias in real time. An efficient inverse kinematics method for simultaneous compensation of RCM bias and end-effector position error is realized by analytical solution. Experiments are carried out on the developed surgical robot platform, the results show that the end-effector positioning error reduce to 0.1426 mm. Compared with the iterative method, the RCM bias is reduced by 92.72% and calculation efficiency increased by 89.97%. The effectiveness of the proposed method is verified, which is of great significance to improve the operation precision and safety of the microsurgery robot.

关 键 词：RCM机械臂 显微手术机器人 运动学标定 误差补偿 逆运动学 

分 类 号：TG156[金属学及工艺—热处理]