Abstract: As to the machining accuracy affected by low stiffness characteristics of the milling robot,the stiffness modeling and error compensation methods of the robot were studied.Above all,with the 6-DOF serial robot ES165D as the research object,the global stiffness model of the robot was established with the consideration of the joint deformation,arm deformation and the influence of arm gravity on the end of the deformation.Through the force deformation test of the robot end,it was obtained that the Mean Absolute Percentage Error (MAPE) between the predicted and experimental deformation of the robot end was less than 15%,which proved the validity and accuracy of the robot stiffness model.The machining path in the milling process was compensated based on the robot stiffness model.The average distance error of the machining path after compensation was reduced by 37.39% compared with that before compensation,which indicated a certain compensation effect.

Key words: milling robot, kinematics analysis, stiffness model, error compensation

摘要： 针对铣削加工机器人低刚度特性影响加工精度的问题,对机器人的刚度建模和误差补偿方法进行研究。以ES165D型号的6自由度串联机器人为研究对象,综合考虑机器人关节变形、臂杆变形和臂杆重力对机器人末端变形的影响,建立了机器人整体刚度模型;通过机器人末端受力变形试验,可知末端变形预测值与试验值的平均绝对百分比误差小于15%,证明了机器人刚度模型的有效性和准确性;基于机器人刚度模型对铣削加工过程中的加工路径进行补偿,补偿后加工路径的平均距离误差相对补偿前降低37.39%。

关键词: 铣削加工机器人, 运动学分析, 刚度模型, 误差补偿