Development of five-finger multi-DoF myoelectric hands with a power allocation mechanism

For use as five-finger myoelectric hands in daily living, robotic hands must be 1) lightweight and human sized as well as possess 2) human-like multiple degrees of freedom (DoF) and a high grip force. The compatibility of these requirements is a trade-off; ideal robotic hands have yet to sufficiently satisfy both these requirements. Herein a power allocation mechanism is proposed to improve the grip force without increasing the size or weight of robotic hands using redundant DoF during pinching motions. Additionally, this mechanism is applied to an actual five-finger myoelectric hand, which can make seven types of motions that are necessary for activities of daily living (ADL) and realizes about a 60% improvement in fingertip force, allowing three fingers to pinch objects exceeding 1 kg.