A measurement and control technology is presented to compensate the movement angle error for each axis of the robot. The effect significance of various factors on the movement angle error is discussed. The control error model of motor moving and the deformation error model of joint or link are analyzed independently. A measuring scheme based on biaxial orthogonal inertial measurement is proposed. In order to obtain the distribution of the space geometric error, the angle error of each robot axis is measured in the motion range of every axis in advance. Then the orthogonal polynomial fitting is used to establish the position error distribution model of each axis. An error compensation value is calculated using the proposed model before the robot runs, so as to control the robot for position compensation. The distribution law of each axis motion error in the robot and the way of orthogonal polynomial fitting are analyzed. The laser tracker is used to measure the compensation effect of the position accuracy of the robot end. The robot control accuracy can be improved by studying robot performance and its compensation.
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