Description of movement of the upper extremities based on anatomical structure model (with special regard to signing gesture)

In the sign gesture, various hand shapes move in a space in front of signer´s upper body, at the same time, change by the side of palm and direction of the top of palm, according to the movements of the arms. In this study, the upper extremity movements used in sign gesture were described by modeling the anatomical structure of the arm movements, and combining the rotation of shoulder, elbow, forearm and wrist joints. Using this model, the range of rotation of each joint involved in the upper extremities was extracted from the video recording of sign gesture, and based on the result, a descriptive system for the upper extremity movement was proposed. It was also shown that, among the possible range of rotation of the upper extremity joints, the range with lesser dynamic work required is used in actual sign gestures