Force-Sensitive Underactuated Three-Finger Robot Hand

Abstract

This paper presents a prototype of a novel three-finger underactuated robot hand with force sensing. It is an electrically-driven high-power gripper with a large grasping force, yet capable of handling both rigid and fragile objects of various shapes and sizes. Its grasp configuration is adaptable to the shape of the object, thanks to its specific linkage-driven power transmission system and the combination of actively and passively (spring-loaded) actuated joints. The hand has 10 degrees of freedom in total, actuated by 4 motors. The novelty of the hand design is reflected in the following aspects: (i) original design and prototype of a three-finger robot hand as a complex mechatronic device, (ii) force sensing based on a custom-designed force sensor integrated into soft fingertips, and (iii) bus communication system with cable-less signal transmission in robot fingers. Signal transmission is based on custom-designed slip ring technology integrated into finger joints, while the bus communication system provides a modular, reconfigurable sensory system.