| The study of flexible robots and parallel manipulators are two important components and advanced topics of robotics. Over the past three decades, the flexible serial robot has developed rapidly due to its light weight, high accuracy and high-acceleration motion, which met the requirements of the development of modern industry. The parallel manipulators provide a new way to improve the performance of robots in terms of lower inertia, higher stiffness and accuracy. Due to the complement to the serial robots in structure and performance, as a result, the application of robot is extended. With the increasing requirements of high precision and high efficiency, the flexible parallel manipulator characterized by both the flexible robot and the parallel manipulator will be a new hot topic in robotics research. Therefore, the research on the flexible parallel manipulator is of great theoretical significance and practical value.In this dissertation, the parallel manipulators and the flexible robots were combined, and the 3-DOF (Degree Of Freedom) spatial parallel manipulators with flexible links were investigated. The dynamic analysis and synthesis of the flexible parallel manipulators, such as dynamic modeling and analysis, virtual prototype simulation, dynamic characteristic and optimal design, and kinematic/dynamic planning etc, were studied and discussed in a comprehensive manner.Firstly, the dynamic modeling and solution of the spatial parallel manipulators with flexible links were studied. A model of spatial flexible beam element was proposed, and the dynamic equations of elements and branches of the parallel manipulator were derived. Using the kinematic and dynamic constraint equations of the parallel manipulator, the overall system dynamic equations of the parallel manipulator were obtained by assembling the dynamic equations of branches. The dynamic responses of the moving platform were analyzed through numerical simulation.Secondly, the virtual prototype simulation of spatial flexible parallel manipulator was derived. The virtual prototypes of 3-RRS, 3-RSR and 3-RRC flexible parallel manipulator were established on the basis of the SAMCEF software, respectively. The displacement error, velocity, acceleration and dynamic stress of these flexible parallel manipulators were analyzed. The comparison results of the numerical simulation and SAMCEF software showed that the effectiveness and correctness of the dynamic models proposed in this dissertation.Thirdly, the dynamic characteristics of the flexible parallel manipulator and design optimization of the parallel mechanism were furtherly investigated. The relationship of the natural frequency and design parameters of the parallel mechanism were studied. Then, the optimal design model of the flexible parallel manipulator based on natural frequency of the system was derived. The motion errors and dynamic stresses are regarded as constraints, and the optimal design of the links parameters was carried out to obtain the parallel mechanism with optimal comprehensive performance.Finally, the input motion programming and dynamic planning of the flexible parallel manipulators were discussed, respectively. The input motion programming and initial configuration selection were applied to decrease the motion error of the moving platform. The dynamic planning was applied to decrease the fluctuation of driving torques.
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