三自由度光學式振動量測探頭之研製與應用

Development and Application of Three-Degree-of-Freedom Optical Vibration Measurement Probe

朱志良(Chih-Liang Chu) ； 黃雅君(Ya-Jun Huang)

《中華民國振動與噪音工程學會論文集》 2012 (2012/06) Pp. 68-75

摘要

本研究主要目的是發展一低成本、高精度的三自由度光學式振動量測探頭。以市售DVD光碟機內之光學讀取頭（Pick-up Head）為光路基礎，將其改良為一自由度量測探頭與二自由度量測探頭。光路設計上，將光學讀取頭之聚焦透鏡鑽一2mm的穿孔，並搭配一偏極分光鏡形成一同軸光路設計。於一自由度量測探頭上，將一雷射光經偏極分光鏡穿過聚焦透鏡上未穿孔的部分，聚焦於待測物表面，用以量測待測物表面的位移變化量，進一步得到Z軸的振動量。於二自由度量測探頭上，令一雷射光經偏極分光鏡折射至透鏡穿孔部分，投射至待測物表面，用以量測待測物表面的兩個角度變化量，進一步得到X與Y軸的振動量。經實驗驗證後，Z軸具有1.71μm的位置標準差數值，量測範圍5μm，而X軸與Y軸分別具有1.69μrad與2.56μrad的角度標準差數值，量測範圍500μrad，且此三自由度光學式振動量測探頭，具有三自由度同點量測之優點。本研究利用此三自由度光學式振動量測探頭，在微細懸臂樑上進行三自由度振動量測，其共振頻率為130.12Hz，將ANSYS分析與實際量測值比較後，其誤差為2.07%。

關鍵字

三自由度振動量測探頭 ； DVD讀取頭 ； 失焦訊號

並列摘要

The purpose of this study is to develop a Three Degree of Freedom Optical Vibration Measurement Probe with a low cost and high precision. This study used the pick-up head from the commercial DVD-ROM as the basis for optical path, and drilled a 2mm hole on the focusing object lens. After combined with the design of a beams plitter, the laser beam source of the 2(two) DVD formed two in-line laser beams. One laser beam passed through the undrilled part, and focused on the surface of the object to be tested, in order to measure the displacement variance of the surface, learned that the z-axis vibration. Another laser beam passed through the drilled hole, and projected onto the object surface, in order to measure the angular variance on the surface.The Measurement probe was tested, and the result verified that the standard deviation of position along Z-axis was 1.71μm with measuring range of 5μm, and the standard deviations of angle of X-axis and Y-axis were 1.69μrad and 2.56μrad, respectively, with measuring range of 500μrad. And Three Degree of Freedom Optical Vibration Measurement Probe, with Three Degree of Freedom measurement of advantages. In this study used the three degree of freedom optical vibration measurement probe to measurements the three degrees of freedom's vibration in the micro-cantilever beam, its resonant frequency 130.12Hz, compare ANSYS analys value with the actual measured values and the error is 2.07%.

並列關鍵字

Three-Degree-of-Freedom Optical Vibration Measurement Probe ； DVD pick-up head ； Focus Error Signal