Abstract: A force/position hybrid control method for polishing the complex surface with an industrial robot is put forward. The method can achieve the stable force control and precise position control to ensure the consistency of the material removal rate at different normal vectors. After the trajectory of the normal vector is planned in CAD software, the force signal feedback from the sensor and the PI controller in the normal vector direction are combined,and the robot end tool corrects the motion trajectory in the vector direction of the surface to indirectly control the contact force between the tool and the surface. As the robot polishing system with different polishing tools has different system stiffness, the adaptive PI control algorithm is proposed and can evaluate the stiffness of the polishing system and adjust the number of PI parameters to ensure the better contact force tracking performance. The simulation and experiment results show that the method can achieve nicely the polishing of the surface part.

Key words: industrial robot, polishing, force/position control, surface part, simulation