【作者】 李研彪；

【导师】 金振林；

【作者基本信息】 燕山大学 ， 机械制造及其自动化， 2004， 硕士

【摘要】 本文对一种新型2-2-2 PTS正交结构六自由度并联机床进行了性能分析。在已有研究成果的基础上，分析了一种由Stewart平台变异而成的新型正交六自由度并联机床的结构特点，论证了这种并联机床在其正交位姿是误差解耦的，选择正交位姿作为机床初始装配位姿，改善了机床的装配工艺性。定义了该种并联机床运动学综合传递性能评价指标和静力学综合传递性能评价指标，并给出了各性能指标在定姿态工作空间内的分布情况。采用微分法建立了该并联机床的误差模型，利用蒙特卡洛技术对终端平台进行了误差分析，并定义了误差灵敏度，以全面评估机床的精度特点。在精度综合工作中，本文采用一种基于蒙特卡洛方法的精度综合，该方法能较好地选择铰链的配合精度，且编程容易。以机床的全域运动学综合传递性能指标、全域静力学综合传递性能指标和全域综合误差指标为评价指标，对该结构机床进行了参数设计。最后，利用计算机技术，对该机床进行了三维动态模拟。本文的研究工作为这种新型并联机床的理论设计和误差补偿提供了理论依据。更多还原

【Abstract】 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.更多还原