A Cosmetic Prosthetic Hand with Tendon Driven Under-Actuated Mechanism and Compliant Joints: Ongoing Research and Preliminary Results

This paper presents recent results aimed at developing a functional prosthetic hand characterized by an EMG-control and by a simple and low cost fabrication technology. In order to overcome some limitations of current prosthetic hands mainly related to the poor functionality and controllability, the prosthetic hand has been designed following a biomechatronic approach based on biologically-inspired design solutions. The core of the project described in this paper is the fabrication of a compliant under-actuated prosthetic hand: the structure of the hand (both palm and fingers) is moulded as a soft polymeric single part with compliant joints and embedded tendon driven underactuated mechanism for providing adaptive grasp. In order to make user trials, the hand is equipped with simple but functional EMG-based control of the single motor incorporated in the hand, and is integrated with a prosthesis socket. The paper presents the biomechatronics design, the fabrication process, the integration of the prosthetic device and first experimental results.