| The terminal actuators, being the final executing manipulator interacting directly with environment, dominate to a great extent the intelligent level and the duty-taking ability of a robot. Much attention has been paid to the research and the development of new robotic terminal actuators for various purposes.The pneumatic artificial muscle is one of such promising robotic terminal actuators and is characterized by direct actuation, simple structure, flexibility, dexterity and high power/weight ratio. Research on it has been carried out by many scholars both abroad and at home, and a primary progress has already been achieved in both academic studies and practical applications. A new type of pneumatic artificial muscle actuator, or flexible pneumatic actuator (FPA), is proposed in the dissertation. Three kinds of joints, namely flexible pneumatic bending joint, flexible pneumatic spherical joint and flexible pneumatic torsion joint are derived from the FPA. A flexible pneumatic artificial finger is then further developed by utilizing three pneumatic bending joints. It is to be applied in the design of the multi-fingered hand. On the basis of systematic summarization and analysis on the state-of-art of the domestic and international robot multi-fingered hands and its related techniques, the research works concerning FPA are mainly focused and carried out as following:For the first step, studies concerning pneumatic artificial actuators abroad and at home are reviewed and comparisons among them are made to summarize the advantages and disadvantages of each actuator investigated. The schematic of FPA is put forward and pneumatic bending joint, flexible pneumatic torsion joint and flexible pneumatic spherical joint are further developed, which aim to simulate the motion of humanjoints.The theoretical and experimental investigation to flexible pneumatic bending joint based on FPA and its control strategy is then succeeded. By the analysis of the bending joint's deformation, its static and dynamic models are established. PID control, fuzzy control and neural PID control are adopted to control the bending joint. Experimental system was also designed to practically obtain the static and dynamic characteristics of the bend joint and its control system under above control strategies. Both theoretical and experimental results demonstrate that while PID control method can sustain a rapid response, the precision is low. Fuzzy control, neural network and other intelligent control techniques can be adopted to improve precision.Parallel to the bending joint, the flexible pneumatic spherical joint is also studied. Static model and dynamic model of spherical joint are built up. A special sensor designed with Hall Elements is used in the position-orientation measurement and control system. PID control, fuzzy control and fuzzy PID control are used in the experiments to realize the effective and efficient control of the spherical joint. Theoretical and experimental results indicate that the performance of the spherical joint is quite similar to that of the bending joint. The PID control method can maintain a rapid response, but sacrifices the precision. Fuzzy control, neural network and other intelligent control techniques are the effective means to enhance precision.Furthermore, the structure and the motion of human finger are studied from the view of surgical anatomy. Experiment was designed to investigate the motions of a single human finger. The motion trajectory, velocity and acceleration of each joint motion are analyzed and discussed. The motion law of human finger is summarized from the theoretical analysis and the experiment.Finally, an artificial flexible pneumatic 3-DOF finger, constructed by three bending joint, is developed and a control system is set up to manipulate its motion. Taking the motion law of human finger as input, the artificial finger is to function as a single human finger. The experimental results prove that the artificial finger possesses the...
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