The robot body error and tool error are finally transmitted to the end of the tool,forming the machining er-ror.The method to improve the machining accuracy is to calibrate all kinds of errors of the robot body,and then calibrate the tool installed at the end of the robot.In this paper,the axis rotation method is used to calibrate the robot body,and the influ-ence of the initial zero value on the calibration accuracy of the robot geometric parameters is analyzed.The kinematic model is established by New Modified-Denavit-Hartenberg(N-MDH)method,the position joint and attitude joint are decoupled,the position joint angle is obtained by analytical method,and the attitude joint angle is obtained by newton iteration method.In the process of tool calibration,the digital model of robot machining equipment is established,and the mapping consisten-cy between the actual equipment and the digital equipment is used to calculate the installation and manufacturing errors of the tool.The New Modified-Denavit-Hartenberg(N-MDH)method can be used to set the base coordinate system and calcu-late the initial zero value easily.The experimental results show that after the initial zero value compensation,the trajectory accuracy of the robot body and tool calibration can reach 0.28mm.
关键词
机器人加工精度/本体与工具标定/初始零位值/新MDH法/映射一致性
Key words
robot machining accuracy/ontology and tool calibration/initial zero value/new MDH method/mapping consistency
维普
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