Robot parameters calibration combining experiment and simulation

WANG Dong1， CAO Tong1， SONG Hu1， LIU Da2， NI Zi-qiang2
（1. School of Mechanical Engineering， University of Science and Technology Beijing， Beijing 100083， China；
2. Robotics Institute， Beijing University of Aeronautics and Astronautics， Beijing 100191， China）

Abstract： Aiming at the problem that the accurate joint paramenters must be obtained by reliable method during medical robot debugging process，the technology of robot calibration conbined experiment and simulation was applied in robot debugging. After the analysis of the structure and kinematics model of medical robt，the relationship between the kinematics model and the joint parameters was established，and the method that conbined experiment and simulation to get the accurate joint parameters was presented. Each joint of the robot was respectively controlled，and the position of tip point was recorded，and the data was processed with the least square method，then the expression of joint axis and the coordinate of the connection point were obtained. So the kinematics model highly consistented with the actual prototype was gotten with simulation，and the accurate joint parameters were obtained with space calculation. The positioning precision was regarded as evaluation index，and the method was repeated used to medical robot for experiment. The experimental results indicate that the final precision of the robot is all locked within 1 millimeter. The method is reliable and engineering practical.
Key words： robot； parameter calibration； precision； simulation