Development of a foldable fivefinger robotic hand for assisting in laparoscopic surgery This study aims to develop a robotic hand that can be inserted into the body from a small incision wound and can handle large organs in a laparoscopic surgery. We determined the requirements for the proposed hand based on a surgeonxe2x80x99s motions in Handassisted laparoscopic surgery(HALS). We identified four basic motions: xe2x80x9cgrasp,xe2x80x9d xe2x80x9cpinch,xe2x80x9d xe2x80x9cexclusion,xe2x80x9d and xe2x80x9cspread.xe2x80x9d The proposed hand has the necessary degree of freedom(DoFs) for performing these movements, five fingers, as in a humanxe2x80x99s hand, and a palm that can be folded into a bellows when the surgeon inserts the hand into the abdominal cavity. We evaluated the proposed robot hand based on a performance test, and confirmed that it can be inserted from a 20 mm incision wound and grasp the simulated organs.

Development of an Adaptive Prosthetic Hand Inspired by biomechanics, an adaptive prosthetic hand which not only considered the function of the motion of the digits but also the palm, is presented in this paper. The human hand consists of different kinds of bones, the phalanges in the digits and the metacarpals in the palm, which cooperate to perform adaptable and dexterous motions. Many existent prosthetic hands focus mainly on the movements of the digits, ignoring the palm. The proposed hand has 15 movable joints in the fingers and the thumb, and 2 movable metacarpals in the palm. The thumb and the four fingers are able to flex independently and adaptively wrap along with the shape of the object. The palm could perform an adaptive holding to some extent through the grasping process, due to the movable metacarpals. Furthermore, the hand design is also considered the weight and size limitations for being used as a prosthesis.