Development of a multi-DOF anthropomorphic prosthetic hand

Based on the underactuated mechanism and coupling principle, a five-fingered prosthetic hand is presented in this paper. The design of the finger is based on two types of four-bar linkage mechanisms. One is the underactuated linkage mechanism, which implements self-adapt grasp with wide variety of objects placed between base joint and middle joint. The other is the coupling linkage which employs between the middle and distal joints. The thumb, the index finger and other three fingers are actuated by a motor respectively. The multi-DOF hand is comprised of 13 joints and driven by three motors. Torque and position sensors are integrated into the fingers. The control system is based on two DSP processing boards. One implements the motion pattern classifier of the hand based on the EMG signals through two electrodes. The other implements the position and torque control of the fingers. All actuators, sensors and electronic boards are embedded into the hand, which presents a highly integrated mechatronics system. Grasping experiments demonstrate that this prosthetic hand has the high grasping capability and dexterity.