The Kineto-elastodynamic Analysis Of A High-speed And Light-weight Parallel Manipulator

A novel 2-dof high-speed and light-weight pick-and-place parallel manipulator with flexible links is presented in this dissertation. The kineto-elatodynamics of this mechanism is studied by finite element method. On the basis of the dynamic model, the performance of the system is optimized. The following creative work has been completed.With the aid of the principle of virtual work, the dynamic model of the robot has been formulated. An approach to estimate the servomotor parameters is proposed using the singular value decomposition technique, resulting in the mapping function between the maximum value of joint variables and the unit operation variables. This makes it possible to estimate the upper bounds of the servomotor parameters in an effective manner. These parameters include the moment of inertia, the maximum speed, torque, and power.According to the characteristics of the parallel manipulator, the dynamic equations of the flexible links and rigid bodies are described in the local coordinates. Then the differential equation of the system is formulated using the kinematic relationships between the links and the rigid bodies. This method avoids repeated modeling for the analysis of different configurations when using ANSYS software, and can be used to investigate the influence of the link parameters on the dynamic performance of the system. The results are useful for the kineto-elastodynamics of a class of high-speed parallel manipulators.On the basis of the dynamic model, the influences of the material and structural parameters of the flexible links on the dynamic performance of the system are discussed and the dynamic characteristics are optimized.The static stiffness and dynamics are analyzed when the moving plate is arbitrarily set in different positions in the working space by the commercial FEM software ANSYS. Since the stiffness in the direction perpendicular to the working plane is rather lower than the other two orthogonal directions, some methods are presented to improve it. These methods have been successfully applied to the development of the prototype machine. The analytic results obtained by ANSYS and modal experiments have validated the dynamic model established above. The theory proposed in this dissertation would be useful for the development of the high-speed and light-weight parallel manipulators.