Kinematics calibration research based on the positioning error of the 6-DOF industrial robot

The forward kinematics model is deduced by combining the D-H method and MD-H method. The Jacobian matrix is deduced by total differential calculation. Thus, a kinematics calibration error model is established in this paper. The positioning accuracy of a SIASUN SR165C industrial robot is improved by using a 24-parameter calibration model. The error model takes into account all geometric parameters. The least square method is used to find the 24 error parameters. The simulation of the robot´s positioning accuracy is performed with 100 points throughout the complete robot´s joint space. After calibrating, the maximum positioning error on the end-effector is reduced from 0.541499 mm to 0.070459 mm, the average positioning error on the end-effector is reduced from 0.225000mm to 0.041075 mm, and the fluctuation of the error decreases.