應用干涉型光纖感測器量測結構衝擊應變響應

The Impact Responses of Structures Measured by the Interferometric Fiber-Optic Sensors

侯錫文(Hsi-Wen Hou)

指導教授 ： 何旭川

元智大學/工程學院/機械工程學系/碩士(2008年)

https://doi.org/10.6838/YZU.2008.00072

摘要

光纖感測器是目前智慧結構中之主要元件之一，不僅在通訊科技方面能有顯著的進步，其高頻寬及低耗損的特性，更能應用於感測與量測。尤其光纖具有直徑小、重量輕、韌性強、抗腐蝕等等優點，對於材料結構上的感測與量測皆具有很大的優勢。本文應用光纖感測器量測結構受到外力衝擊作用後之應變響應，結合光彈理論與Mach-Zehnder干涉推導出光相位差與應變關係，應用3x3光耦合器三個輸出端各具120ﾟ相位差之特性，配合Matlab軟體中的SIMULINK數學運算軟體，將光訊號加以分析並反算出結構應變，並與應變規量測所得比較。實驗使用之外力包含衝擊鎚敲擊與自由落體掉落，試片則包含樑與板兩種結構，試片夾持方式為單邊固定及雙邊固定兩種模式。探討衝擊鎚敲擊不同位置和不同落下高度之衝擊響應，將光纖感測之結構應變與應變規量測值比較，驗證光纖量測結構暫態響應之準確度與可行性。

關鍵字

光纖感測器 ； Mach-Zehnder干涉儀 ； 衝擊響應 ； 衝擊鎚 ； 落下測試

並列摘要

Fiber-Optical sensors with small dimension, light weight, low loss and wide bandwidth, have been widely used in the smart structures. In this work, the Fiber-Optic sensors are employed to measure the impact responses of beam and plate structures by using the Mach-Zehnder interferometric technique. The beam and plate are subjected to the impact via a impact hammer and drop test. The strain responses measured by the fiber-optic sensor are validated with the strain gauge. Good agreements between the fiber-optic sensor and strain gauge demonstrate that the fiber-optic sensor is capable of measuring the transient response of the structures.

並列關鍵字

fiber-optic sensors ； Mach-Zehnder interferometry ； impact response ； impact hammer ； drop test

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