Development of a biomimetic robot hand with faithful bone reproduction and simplified soft-tissue constraints

Abstract Biomimetics is one of the promising approaches for reproducing the human hand by robotics. However, due to its structural complexity, comprehensive imitation remains challenging, and a five-fingered biomimetic robot hand applicable to real tasks has yet to be fully realized. Therefore, this study aims for faithful reproduction of bones’ geometry based on a human hand skeleton model while adopting an engineering simplification for muscle, tendon, and ligament by a silicone rubber membrane. This simplification lacks biological faithfulness but defines relative positions/motions of bones similar to them of the human hand. This paper describes the design and fabrication procedures of the developed biomimetic robot hand in detail. Through evaluation experiments of the developed hand, the realization of thumb opposition and sufficient grasp stability based on quantitative evaluation were confirmed. These results demonstrate the validity of the proposed approach.