A novel design of a prosthetic hand

An innovative prosthetic hand prototype is presented in this paper. To increase the grasping stability, an underactuated finger is embedded in a traditional gripper. There are a total of three motors employed in the hand system: the gripper, the embedded finger, and the wrist. The preliminary performance shows that this prosthetic hand is capable of performing various daily jobs such as turning a key, pinching a card, grasping tubes of various sizes, etc. The maximum grasping force for the gripper is about 2 kg and that for the embedded finger is about 0.3 kg. The closing time for both the gripper and the embedded finger is about 0.2 sec, which is relative fast among similar prosthetic hands. The performance of this innovative prosthetic hand prototype shows the idea of the embedded finger is promising and further improvements will continue.