This paper proposes a 6R robot closed-loop kinematic calibration method to improve absolute position accuracy with point and distance constraints though machine vision. In the calibration process, a camera attached to the mounting plate of the robot is used to capture a fixed reference sphere as a point constraint and to record robot joint angles and gauge block lengths that are used as a distance constraint. A first-order difference quotient is used to calculate the Jacobian matrix in the joint parameter identification process. The Staübli TX60 robot is successfully calibrated using the proposed method. After calibration, the average distance error of robot motion is decreased from 2.05 mm to 0.24 mm.

本文提出了一种6R机器人闭环运动学标定方法，以通过机器视觉提高受点和距离约束的绝对位置精度。在校准过程中，使用连接到机器人安装板上的摄像头捕获固定的参考球体作为点约束，并记录用作距离约束的机器人关节角度和量块长度。在联合参数识别过程中，使用一阶差分商来计算雅可比矩阵。使用所提出的方法成功校准了StaübliTX60机器人。校准后，机器人运动的平均距离误差从2.05 mm减小到0.24 mm。