Kinematic Design Of 2-PP_a Translational Parallel Manipulator

This thesis focuses on the kinematic optimum design of the two kinds of 2-PPa translational parallel manipulators: vertical manipulator and horizontal manipulator. The main works and research results are as follows.According to the placement of path, there are two kinds of 2-PPa translational parallel manipulator: vertical manipulator and horizontal manipulator. To avoid interference of the manipulator, as to enlarge its workspace, the designer adds an accessory to the slide to enlarge its angle .On the base of the manipulator diagram, the configuration parameters are defined. The frames of reference of the fixed part and moving platform are established. Based on the above analysis, the forward and inverse kinematic models are formulated. In the foundation of forward and inverse kinematic models, the mapping matrix of speed from drive joint to the output of the moving platform, namely speed Jacobian matrix is proposed. Using inverse displacement and Jacobian matrix to calculate the determinant of the Jacobian matrix concerning each pose, the solution of singular configuration is obtained. Through the analysis of the expression of Jacobian matrix, necessary condition at the singular configuration of two kinds of 2-PPa translational parallel manipulator is proposed.Based on the relationship of required workspace and the two kinds of 2-PPa translational parallel manipulator, the relation functions of the limiting position angle and structural parameters are studied. From the perspective of kinematics and statics, the mapping model of speed ,load, condition, stiffness from drive joint to moving platform are formulated and all the indices concerning speed, load, condition, stiffness are defined. With the area ratio of the manipulator and the required workspace, we can avoid the material waste. At last, all above indices are combined into a synthesis index. According to the size range of the structural, assembling parameters, interference angle and required workspace, the atlases of global performance are presented. Optimal design of the structure is implemented according the atlas of global performance. Using GUI tool of Matlab, the information of 2-PPa translational parallel manipulator as well as the atlases of global performance are integrated to one application model which provides convenience to the designer.On the result of optimum design, the virtual prototypes are established by SolidWorks and ADAMS software. The displacement, velocity and acceleration of moving platform are studied based on the virtual prototype.On the kinematic anlysis of the virtual prototype, the prototypes are manufactured. And a motion control system is built by the NI Company's PCI-7340 motion control card and Haydon stepping motor. The movement of moving platform is moved by order path, and the purpose of the experiment is achieved.The achievements stated in this thesis lay a solid foundation for the development of 2-PPa translational parallel manipulator.