布拉格光纖光柵感測器之理論分析以及應用於動態量測與監測之探討

The Theoretical Analysis of Fiber Bragg Grating Sensor and Application to Dynamic measurement

王兆祥(Chao-Hsiang Wang)

指導教授 ： 馬劍清

國立臺灣大學/工學院/機械工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.00331

摘要

FBG（Fiber Bragg Grating）感測器因為有許多優良的機械性質，近年來成為一個廣泛運用的感測器，然而若是單純使用其光學特性進行量測，無法進行短時間內劇烈變化的動態或是暫態量測，而能量調變法的出現，不僅讓FBG感測器可可進行暫態或是高頻量測，對於量測的精度亦有所提升。
本論文首先模擬分析不同的感測器與綠波器的搭配產生之不同的量測結果，並且與實際的實驗結果做驗證。而且為了能夠更進一步的探討感測器在短時間內的動態解析能力，本文選取此感測器安裝在懸臂樑系統上進行回授控制；而為了探討其訊雜比以驗證此感測器是否能夠監測系統不連續訊號，本文也將其安裝在一個承受移動負載的軌道系統進行量測。
綜觀整篇論文，可以看出FBG能量調變法確實為優秀的感測器，不僅可以進行面外的位移量測，也可以量測待測物的面內應變。此外，其訊雜比載面外量測方面優於現在常用的光纖位移計，面內應變量測則優於應變規。

關鍵字

FBG感測器 ； 高斯函數法 ； 懸臂樑 ； 振動控制 ； PPF控制器 ； Simulink ； dSPACE ； 光纖位移計 ； 移動負載 ； 軌道

並列摘要

Because FBG sensors have many excellent mechanical properties, recently, they have become widely used sensors. However, if we only use FBG sensors’ optical properties doing measurements, then, we can’t do drastic dynamic or transient measurements in short time. Therefore, when demodulation appears, not only can we use FBG sensors doing transient or high-frequency measurements but also can we improve the accuracies of measurements.
The first part of this essay analyzes simulations of measurements composed of different sensors and filters, and simulations will be verified to experiment results. Additionally, in order to study sensor’s dynamic resolution in short time further, this essay chooses to install sensors on cantilever beam system to do feedback control. Moreover, in order to study FBG sensors’ signal to noise ratio which verify whether FBG sensors monitor discontinuous signals or not, the essay installs FBG sensor on a rail system subject a moving load or a moving mass to do the measurements.
All in all in this essay, FBG demodulation is truly a splendid sensor. It can address the displacement measurement of out-of-plane as well as in-plane strain of object measurement. Furthermore, its signal to noise ratio of out-of plane measurement is superior to Fotonic sensor which is now generally used, and in-plans strain measurement is superior to strain gauge.

並列關鍵字

FBG sensor ； Gaussian function ； cantilever beam ； vibration control ； PPF controller ； Simulink ； dSPACE ； Fotonic sensor ； moving mass ； rail

參考文獻

[34] 葉耀文，馬劍清, "短週期光纖光柵在動態系統的量測與應用," 碩士論文, 機械工程學研究所, 臺灣大學, 2004.

[39] 汪政緯，馬劍清, "應用布拉格光纖光柵感測器於結構件承受撞擊之暫態應變量測," 碩士論文, 機械工程學研究所, 臺灣大學, 2008.

[40] 莊國志，馬劍清, "多維高解析度布拉格光纖光柵動態位移及應變量測系統之研發並應用於暫態波傳之量測," 博士論文, 機械工程學研究所, 臺灣大學, 2008.

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