无导轨高精度位移平台的结构设计

Structure design of precise displacement platform without guiding apparatus

为了完善高精度位移平台性能,提高平台位移直线度和定位精度,研制了制造成本较低的高精度无导轨位移平台机构。根据平行四边形和比例杆运动原理,设计了无导轨平台结构。介绍了平台的工作原理,并对其运动部件进行了有限元分析。用自准直平行光管和高精度测量头分别检测了平台的位移直线度和升、降位移误差,实验结果得出,该机构的位移直线度误差小于1",升、降位移误差小于0.02 mm,达到了平台设计要求。应用结果表明,该平台安装方便、体积小、易于养护,在有无重力的条件下均能正常使用,可应用于航天或其它领域的高精度位移系统中。

A new low-cost precise displacement platform without a guiding apparatus was developed to perfect its working performance and to improve the displacement straightness and position accuracy of the system. Based on the theories of parallelogram and proportional lever, the structure of the platform was designed and the work principle was introduced. Then,the movement parts in the platform were analyzed by the Finite Element Method（FEM）. Finally, an autocollimator and a high precise measuring head were used in the measurement of the displacement straighness and the the error of the lifting displacement, respectively. The experiment results show that the error of the displacement straighness is smaller than 1″ and the error of the lifting displacement is less than 0.02 mm, which shows that the structure achieves the design desire completely. The platform in applications is proved that it is easy to install and maintain and can be used in a weightless condition, so it is suitable for the spaceflight fields and other precise displacement systems.