超精密定位平台撓性結構之研究

Abstract

摘要 現今位移平台大部分以四組壓電塊控制三個自由度較為廣泛，若減少一組壓電塊來控制三個自由度且不降低原有功能，必能減少成本開銷，故本研究以一組壓電塊控制一軸自由度為目標，且參考各類之論文不難發現以旋轉定位平台幾乎都是使用兩組壓電塊來達成旋轉定位平台之功能。故本研究以旋轉定位平台之分析為主軸，是以槓桿原理固定端與施力端來設計旋轉定位平台，施加電壓於壓電材料使旋轉定位平台之結構變形產生位移，並用田口方法決定位移平台最佳尺寸達成定位精度。 本研究將奈米定位平台的分析與設計結果應用於光學領域上。用田口式和有限元素分析來得之設計尺寸，實作出旋轉定位平台，並以兩種方式搭配作檢測： 1.給予某一定電壓，使壓電塊產生形變，將感測信號傳至回饋式功率放大器，從而得知所產生的位移。 2.藉由麥克森干涉系統以干涉條紋可以得知位移量。 檢測結果與模擬數據吻合。 關鍵詞：精密定位平台，撓性結構、田口方法、有限元素分析。Abstract In general, positioning platform with three degrees of freedom utilizes four piezoelectric pieces to achieve its motion control. The reduction of the number of piezoelectric pieces will decrease the costs dramatically. This study aims at the design and analysis of flexible structure of positioning platform with lesser number of piezoelectric pieces to give the rotation capability. In this study, the level principle is used to design a rotating mechanism in positioning platform. The deformation of flexible structure caused by piezoelectric pieces due to applied voltage gives rotating motion. The stress and deformation of positioning platform for different designs are analyzed by method of finite element, then Taguchi method is used to choose the optimal size of platform to achieve the desired displacement accuracy. The results of design study are applied to implement a rotating positioning platform used in optics field. The performance is examined by two ways: 1.For a given voltage, the deformation of piezoelectric block is sensed and its signals are transmitted back to get the displacement. 2. McKesson interference system to measure the displacement

The test results coincide with the simulation data within acceptable range. . Keywords：Precision positioning platform, Flexible structure, Taguchui method, Finite element method.