Development of a Lightweight Prosthetic Hand with Tendon-driven Five Fingers

This paper proposes a lightweight prosthetic hand with tendon-driven five fingers. Each finger is composed of a distal-middle phalange, a proximal phalange and a metacarpal bone, which are connected to a link mechanism. The finger flexion is a resultant motion by pulling a wire to serve as a tendon, but the finger extension is performed by an elastic mechanism composed of a restoration spring. The developed hand has six degrees of freedom. But its total weight is merely 400.72g. The hand performs various hand functions such as the grasping and the hand postures. From experimental results, we show that the proposed prosthetic hand is applicable to amputees as a prosthetic hand.