Development of a polishing robot system

This paper presents the development of a robot-assisted surface finishing system with an active force controller. The system utilizes a dexterous manipulator to attain the desired position and orientation in 3D space during finishing processes. This single-axis force controller consists of a DC motor and a software observer. The DC motor is attached to the robot wrist and used to actuate a pneumatic hand-grinder. The force observer is designed to sense the grinding contact-force based on the driving current and output position of the motor. The function of the active force controller includes observing the polishing contact force, applying a desired polishing pressure in the normal direction of the workpiece surface, and adjusting the contact angle between the hand-grinder and the surface of the workpiece. In this research, the prototype of a robot-assisted polishing system is constructed and tested on a Tatung A-530 robot. The experimental results show that the robot-assisted polishing system functions well under a variety of grinding and polishing conditions.