A Quasi-Direct Drive Robot Hand for Reactive and Contact-rich Manipulations

Abstract

Proprioceptive actuation, which includes direct-drive (DD) and quasi-direct-drive (QDD), has achieved great success in the legged robots community recently. It also shows great potential in reactive and contact-rich manipulations. However, it suffers from critical problems such as motor overheating and unacceptable low firm grasping force, which prevents its further applications. To solve these problems, this paper presents a novel QDD hand design with an innovative hybrid drive mechanism that can take full advantage of grasping mode characteristics, thereby significantly increasing the grasp force without overheating the motor. We present detailed design, formulate the kinematics and dynamics modeling, investigate current-based force sensing (proprioceptive perception) and associated control strategies. We develop an integrated robot arm-hand system and perform experiments to validate the effectiveness of our proposed approach. Experimental results indicate that our proposed design holds great promise in leading a fundamental paradigm shift in robot hand design.