Development of a force controlled robot for grinding, chamfering and polishing

This paper presents a force controlled robot system for grinding, chamfering and polishing in machining plants. To facilitate easy operations, a task-oriented robot language and a force control method for following edges of workpieces have been developed. In the task-oriented robot language, a task is declared first by a task name, a tool code and a tool center point. The tool center point is a position in contact with a workpiece. These indexes and a force control motion command determine the parameters for the force control of the robot. The workpieces for grinding, chamfering, and polishing almost always differ their setting position, their size and/or their shape each by each even when the workpieces are the same parts in a machine. To cope with such workpiece difference, a tool moment control method, a skip function, and a round function have been developed. The experiments chamfering of the edges of a part in an injection molding machine are reported.