A Novel Design Of Two Degrees Of Freedom Imitating Human Upper Extremity And Study On Pneumatic Actuator

With the development of technology, an actuator that is powerful, lightweight and compliant and can be operated in a manner similar to human muscles is needed in the study of robots. The Humaniform Air Muscle (HAM) is one of such novel actuators with many advantages. The Humaniform Muscle overshadows McKibben style actuators in many aspects.The design of a 2 degrees of freedom imitating human upper extremity is proposed in this thesis. This dissertation is financially supported by the National Natural Science Foundation of China (project No. 50375108) and the Natural Science Foundation of Tianjin (project No.033601611). The main research work in this thesis includes:Based on the analysis of the anatomy structure of human upper extremity, the upper limbs are simplified as a motion system of two rigid bodies, the joint of forearm with humeral as a hinge. With the freedom in adduction and abduction motions of shoulder joint, a two-rigid-body motion system is formed.The large number of assumptions made in deducing the ideal model of the Humaniform Air Muscle result in significant differences between the ideal model and the real attributes of the Humaniform Air muscle. Therefore, the main factors affecting the ideal model including the elasticity and wall thickness of the rubber tube, its shape at both ends and the friction between the rubber and braided net, are analyzed. An improved model is proposed.A new type test-bed for HAM has been built. On this test-bed, all the measurement and control can be carried out by computer. The validity of the theoretical models is tested on the test-bed.A test-bed for imitating human upper extremity has been established. Experiments on the static and dynamic behaviors of the extremity were conducted. At the end, the future research work on HAM and imitating human upper extremity is analyzed and discussed.