Contact force control and vibration suppression in robotic polishing with a smart end effector

Abstract Polishing of thin-walled blisks can easily lead to vibrations and affect the surface quality. To solve this problem, we present a novel smart end effector for active contact force control and vibration suppression in robotic polishing of thin-walled blisks. A gravity-compensated force controller is developed to maintain the contact force between the polishing tool and the workpiece to an expected value. Two novel eddy current dampers are designed and integrated into the smart end effector to improve the system dynamics and suppress the vibrations. The principles of the contact force control and vibration suppression with the smart end effector are explained. Experimental results show that the presented smart end effector reduces the contact force variation in the robotic blisk polishing from 8 N to less than 1 N, and significantly suppresses the spindle vibrations, therefore, leading to a better surface quality.