A Biomimetic Compliance Control of Robot Hand by Considering Structures of Human Finger

Abstract

In this paper, for an object grasped by a robot hand to work in compliance control domain, we first analyze necessary condition for successful stiffness modulation in the operational space. Next, we propose a new compliance control method for robot hands which consist of two steps. RIFDS(Reso1ved Inter-Finger Decoupling Solver) is to decompose the desired compliance characteristic specified in the operational space into the compliance characteristic in the fingertip space without inter-finger coupling, and RIJDS(Reso1ved Inter- Joint Decoupling Solver) is to decompose the compliance characteristic in the fingertip space into the compliance characteristic in the joint space without inter-joint coupling. According to the analysis results, the finger structure should be biomimetic in the sense that either kinematic redundancy or force redundancy are required to implement the proposed compliance control scheme. Five-bar fingered robot hands are treated as illustrative examples to implement the proposed compliance control method. To show the effectiveness of the proposed compliance control method, simulations are performed for two-fingered and threefingered robot hands.