The Combined Measurement and Compensation Technology for Robot Motion Error

Robot parameter errors are mainly caused by the kinematic parameter errors and the moving angle errors. The calibration of the kinematic parameter errors and the regularity of each axis moving angle errors are mainly researched in this paper. The errors can be compensated by the error model through pre-measurement. So robot kinematic system accuracy can be improved in the case where there are no external devices for real-time measurement. Combination measuring system which is based on the laser tracker and the biaxial orthogonal inertial measuring instrument is designed and built in the paper. The laser tracker is used to build the robot kinematic parameter error model which is based on the minimum constraint of distance error. The biaxial orthogonal inertial measuring instrument is used to obtain the moving angle error model of each axis. The model is preset when the robot is moving in the predetermined path to get the exam movement error and the compensation quantity is feedback to robot controller module of moving axis to compensation the angle. The robot kinematic parameter calibration bases on distance error model and the distribution law of each axis movement error are discussed in this paper. The laser tracker is applied to prove that the method can effectively improve the control accuracy of the robot system.