A Fundamental Force Control Method and Individual Task Control Methods for Finishing Tasks.

Adequate force control is essential in the manipulators of finishing robot systems. However, it is difficult to design an effective force control method for each finishing task because finishing processes consist of various different individual tasks. In this paper, a fundamental force control method for finishing tasks, which is based on position control, is shown first. We classify finishing tasks into four types ; surface-smoothing tasks, edge-smoothing tasks, protuberance-removing tasks, and cutting tasks. In each of the individual tasks, the force control method, force control direction, and force detecting direction are examined. Then, two types of force control methods are proposed for finishing tasks. In the first method, the force control direction is perpendicular to the tool feed direction. This method is called grinding force control. In the second method, referred as cutting force control, force control is performed in the tool feed direction. Finally, we outline the principles that guide selection of the force control method, force control direction, and force detecting direction for individual finishing tasks.