Characteristics Analysis And Mechanical Implementation Of Human Hand Movements

An ideal prosthetic hand should be both visually similar to the authentic hand and satisfactory to the basic daily life requirements of the handicapped. Based on this, an ideal prosthetic hand should possess a pleasing profile and compact structure, etc. However, for now, there is no prosthetic hand system at home and abroad that can meet the requirements. Therefore, this paper designs a prosthetic hand system from the following aspects:(1) An experimental paradigm for the human hand motion is set up. Based on it, data gloves are adopted to collect the data of human hand motion. After conducting the principal component analysis of the human hand motion data, the mechanical principles of human hand grasping movement, as well as the characteristics of the synergic movement of human hands are discovered. Moreover, the paper also studies the correlation between human fingers, including kinematic relation between finger joints, kinematic relation between fingers, and the synergic features between fingers.(2) The paper describes the design details of a kind of prosthetic arms, including the finger design and the driving mechanism. In the design of prosthetic arm fingers, the paper focuses on the finger joints design and simplification. Springs are imbedded into the fingers to realize the self-adaptive functions. In the design of driving mechanism, in order to represent the human hand motion spectrum, the motion is decomposed into proportional movement and scaling movement, and realized by mechanical methods, which is different with the traditional linear superposition method. Lastly, the overall design layout of the prosthetic arm is introduced.(3) The paper elaborates the experimental process of the prosthetic arm. The most characteristic grasping modes are selected to conduct the grasping experiments. The grasping performance of the prosthetic arm and the feasibility of the design methods are verified. Lastly, the gripping ability of the prosthetic arm is evaluated through gripping tests, for making references for the next generation design of prosthetic arms.