基于机械关节反馈的机器人精度补偿技术

Accuracy Compensation Technology for Robot Based on Mechanical Joint Feedback

工业机器人因其高柔性和低成本而正被越来越多地应用于飞机自动化装配生产线中,但其绝对定位精度差一直是制约其发展的瓶颈。为了进一步提高机器人末端的定位精度,提出了基于机械关节反馈的机器人定位精度补偿方法,该方法通过在机器人的关节处安装绝对式光栅尺,将关节伺服引入到机器人的控制中,来实现机器人关节的闭环控制,从而降低关节误差对末端位置的影响,提高关节的定位精度。试验结果表明,机器人的绝对定位误差由补偿前的最大值1.125mm降低到0.167mm,该方法能够有效地降低机器人的绝对定位误差,实现机器人的高精度控制。

Industrial robots have been increasingly applied to aircraft automation assembly lines due to their highflexibility and low cost, but poor absolute positioning accuracy of industrial robot is the bottleneck that constrains theirdevelopment. In order to further improve the positioning accuracy of the robot, a positioning accuracy method based onmechanical joint feedback is proposed. This method is applied to control the robot by installing the absolute gratings at thejoints and the semi-closed-loop control is established for reducing the effect of the joint error on the position of the end effectorand increasing the positioning accuracy of joints. The experimental result shows that the absolute error of the robotis reduced from 1.125mm to 0.167mm. This method can effectively improve the absolute positioning accuracy of the robotand realizes the high precision control of the robot.