Design of robotic hand with tendon-driven three fingers

This paper proposes a robotic hand with tendon-driven three fingers that consist of a thumb, an index, and a middle finger. Each finger is composed of a distal-middle phalange, a proximal phalange, and a metacarpal bone, which are jointed by one link between the distal-middle phalange and the metacarpal bone. The flexion of finger is actuated by a wire to serve as a tendon of finger. By pulling the wire using DC motor, the proximal phalange is actuated, and then the distal-middle phalange is actuated synchronously by the link mechanism. The finger extension is performed by a restoring spring. The designed hand with the tendon-driven fingers is executable various hand motions such as direction, grasping, scissors and rock postures. Experimental results show the designed robotic hand is applicable to hand prosthesis for amputees.