The Performance Analysis On A Novel 6-PTS Parallel Machine Tool

The thesis focuses on the performance research on a novel type of 2-2-2 PTS orthogonal parallel machine tool.A novel structure of 6-DOF parallel machine tool based on the Stewart platform mechanism is developed and its layout feature is presented according to the previous research results. The paper also shows that the novel parallel machine tool is characterized by decoupling error at its orthogonal position. By means of choosing the orthogonal position as the initial assembly position the assembly technological efficiency of the parallel machine tool is improved.kinematics transmission evaluation critieria,mechanics transmission capacity evaluation critieria are defined. The distribution of the defined evaluation critieria of the 6-PTS parallel machine tool are presented on the constant-orientation workspace. The error model of the parallel mechanism using a differential method is developed. The distribution on terminal platform errors is discussed using Monte-Carlo method, Moreover, error sensitivity is defined which is useful for the accuracy analysis. In the process of accuracy synthesis, Mente-Carlo method is used for calculating the moving platform's mean error. The results show that this method is simply and easy to program.Based on the workspace of a new 6- PTS parallel machine tool, geometry parameter of the parallel mechanism is optimized which depend on the glob kinematics,the glob mechanics and the glob equal errors.The research in this paper are very useful for the design and error compensation of the parallel machine tool.