2-UPR-SPR并联机构的刚度与谐响应分析

目的针对一种两转一移三自由度封装并联机构2-RPU-SPR自动化包装过程中高工作精度的特殊应用要求,运用有限元法对其进行刚度与谐响应分析,从而研究机构的刚度和抗振性能。方法运用Solid Works建立三维实体模型,然后导入Ansys Workbench软件进行分析。结果得到机构在外力作用下3种不同姿态的位移变形云图,并通过模态分析,得知2-RPU-SPR并联机构1—6阶固有频率分别为130.39,133.42,218.35,760.36,768.07,776.96 Hz,以及各阶频率下的振型。在此基础上进行谐响应分析,得出动平台在x,y,z轴方向的位移响应曲线。结论找出了机构刚度的薄弱部位,得出了刚度随位姿变化的规律;通过谐响应分析验证了该并联机构的抗振性能,得出机构应避免的敏感频率,这为该封装并联机构的进一步动态设计与优化奠定了基础。

Stiffness and Harmonic Response of 2-UPR-SPR Parallel Mechanism

The work aims to analyze the stiffness and harmonic response of package parallel mechanism of 2-UPR-SPR which has three degrees of freedom including two turns and one move, thus researching the stiffness and anti-vibration performance of the mechanism, with respect to the special application requirement of high working precision in the process of automatic packaging. The 3D entity model was established by SolidWorks and then imported into software Ansys Workbench for analysis. The displacement deformation cloud of the mechanism under three different postures on the action of external force was obtained. Through the modal analysis, the natural frequencies from first order to sixth order of 130.39, 133.42, 218.35, 760.36, 768.07, 776.96 Hz and the vibration mode of each order frequency of the 2-UPR-SPR parallel mechanism were obtained. On the basis of modal analysis, the displacement response curve of platform along x, y, z directions was deprived by harmonic response analysis. The weak position of mechanism stiffness can be seen, and the rule of the change of stiffness with the position is obtained. The anti-vibration performance of the parallel mechanism is proved by harmonic response analysis, and the sensitive frequency that the mechanism should avoid is got. It lays the foundation for further dynamic design and optimization of the package parallel mechanism.