Abstract: A 3D vision based robot polishing path planning method was proposed aimed at improving the accuracy and efficiency of robot polishing. Firstly,the structured light camera was used to obtain point cloud data on the surface of the workpiece. The RANSAC algorithm was used to remove the background,and the point cloud slicing algorithm was used to divide the row spacing. Subsequently,the Douglas-Peuker algorithm was used to dilute the path points,and the normal was calculated based on direct estimation method to generate accurate polishing path. In order to achieve stable force tracking,an adaptive variable impedance control strategy was designed. The performance of PID control method,constant impedance control method and adaptive variable impedance control method in planar,curved and complex surface environments was compared using the MATLAB Simulink simulation platform. The simulation results showed that the proposed adaptive variable impedance control method was superior to traditional methods in terms of force tracking accuracy and response speed. In the simulated polishing experiment,a polishing system based on FANUC M-10ia/12 robot and CX5020-0111 controller was built. The experiment verified the effectiveness of this method on surfaces of workpieces with different shapes,especially in complex curved environments.

Key words: path planning, RANSAC algorithm, force tracking, adaptive variable control, complex surface