Hybrid position/Force control for coordination of a two-arm robot

Abstract

In this paper we discuss the control of cooperating tasks being done by two robotic arms. In order to control those tasks, we extend hybrid position/force control scheme presented thus far by various researchers for a single-arm robot. The point of the extension is formulation of kinematics and statics for a two-arm robot which is new in this paper. We define a unique system of workspace coordinates and, corresponding to the unique workspace, introduce an unique jointspace vector consisting of joint-vectors of the two arms. Using these work and joint spaces, we formulate kinematics and statics. Based upon this formulation, we successfully apply the hybrid scheme to the two-arm robot. A demonstration of the theory working on a real two-arm industrial robot and experimental data of simultaneous control of position and force proves the effectiveness of our method.