光纖光柵量測結構應變與溫度及水位監測研究

Experimental measurements of mechanical strain, temperature change and water level using fiber Bragg grating sensors

林威男(Wei-Nan Lin)

指導教授 ： 何旭川

元智大學/工程學院/機械工程學系/碩士(2011年)

https://doi.org/10.6838/YZU.2011.00357

摘要

光纖光柵承受機械應變與溫度變化所產生之反射波長偏移，可用於量測結構應力、應變、位移、溫度、振動與壓力等物理量。本文以光纖光柵結合光譜儀可同時量測結構承受之應變與溫度並將量測結果分別與應變規及熱電偶比較，驗證量測之準確性。另再結合光濾波器與光偵測器，將光纖光柵反射光波長變化轉換為光強度變化，可用於量測結構動態變化。並以動態三點彎曲與四點彎曲實驗及懸臂樑自由振動，驗證光纖光柵量測結構動態響應之可行性。最後將光纖光柵感測器，應用於量測水位高低及水面之動態波動變化。

關鍵字

光纖光柵 ； 布拉格反射波長 ； 光濾波器 ； 光強度 ； 動態響應

並列摘要

Basing on the shift of Bragg wavelength, fiber Bragg grating sensors (FBG) have been developed to measure a variety of physical parameters such as stress, strain, displacement, temperature, vibration and pressure. In this work, the FBG was connected to an optical spectrum analyzer (OSA) to measure the mechanical strain and temperature change simultaneously. The measuring results were validated with the strain gauge and thermal couple. In order to measure the dynamic responses, the FBG was incorporated with the optical filter and photo detector to convert the shift of Bragg wavelength to a change of light intensity. The experimental tests of dynamic three point bending test, dynamic four point bending test and free vibration test of a cantilever beam were presented to demonstrate the capability of measuring dynamic responses using FBG sensors. Finally, the FBG sensor was used to monitor the water level subjected to a wave motion.

並列關鍵字

dynamic responses ； fiber Bragg grating ； Bragg wavelength ； optical filter ； light intensity

參考文獻

[12]. 周志成，”應用光纖光柵感測器量測結構應變、溫度及振動”， 元智大學機械工程研究所碩士論文 (2006)

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