內埋干涉型光纖感測器結構分析與量測研究

Structure analysis and measurement study of fiber optic sensor embedded composites

陳汶鋅(Wen-Hsin Chen)

指導教授 ： 何旭川

元智大學/工程學院/機械工程學系/碩士(2002年)

摘要

結構藉由內埋之光纖感測器，偵測內部溫度、應變與應力，監控結構之使用狀態，大幅提昇結構功能與價值。本文研究內埋光纖感測器複合材料結構之力學行為與量測原理。力學分析主要探討光纖內埋對原結構應力場及應變場之干擾，應用Lehnitskii應力函數推導結構遠場應變與內埋光纖應變之關係。量測部份則就不同類型的干涉型光纖感測器，包含Intrinsic Fabry-Perot和In-Line Fiber Etalon等，應用光彈及熱光理論推導光纖應變和溫度所造成的光相對相位變化量與光強度變化。比較光纖感測器貼覆與內埋兩種不同放置方式，量測結構應變、溫度之差異性，並以結合兩種感測器方式同時量測結構應變與溫度。最後將In-Line Fiber Etalon光纖感測器應用於複合材料層板承受撞擊，量測撞擊接觸力與時間。

關鍵字

複合材料結構 ； 光纖感測器 ； 應力函數 ； 光彈理論 ； 光相對相位量 ； 撞擊

並列摘要

By using the embedded fiber optic sensor, structure is able to detect its own temperature, strain and stress, monitor its working status, and substantially increase the performance and application. In this investigation, the mechanical behavior and measurement performance of the fiber optic sensor embedded composite structure have been studied. The structural analysis is focused on the interfered stress and strain fields arising from the embedded fiber optic sensor. Lekhitskii stress functions were adopted to derive the relation of the strains in the host structure far from the optic fiber to the strains inside the optic sensor. Various interferometric fiber optic sensors such as Intrinsic Fabry-Perot and In-Line Fiber Etalon, have been presented to study the measurement performance. By using the photo-elasticity theory and thermal photo theory, the expression of the changes of the relative phase and the intensity of the reflected light induced by the temperature and strain inside the optic fiber were developed. The measurement performance of the embedded sensor was compared with the surface mounted sensor. In this investigation two sensors were combined to measure the temperature and strain simultaneously. Application of the In-Line Fiber Etalon sensor on measuring the impact force and duration of composite laminate is also presented.

並列關鍵字

composite structure ； optic fiber sensor ； stress function ； photo-elasticity theory ； relative phase change ； impact

參考文獻

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