Strain Monitoring using Distributed Fiber Optic Sensors Embedded in Carbon Fiber Composites


A distributed fiber optic strain sensor based on Rayleigh backscattering, embedded in a fiber-reinforced polymer composite, has been demonstrated. The optical frequency domain reflectometry (OFDR) technique was used to analyze the backscattered signal. The shift in the Rayleigh backscattered spectrum (RBS) was observed to be linear to the change in strain of the composite material. The sensor (standard single-mode fiber) was embedded between the layers of the composite laminate. A series of tensile loads were applied to the laminate using an Instron testing machine, and the corresponding strain distribution of the laminate was measured. The results show a linear response indicating a seamless integration of the optic fiber in the composite material and a good correlation with the electrical-resistance strain gauge results. In this study, distributed strain measurements in a composite laminate were successfully obtained using an embedded fiber optic sensor.

Meeting Name

SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring (2018: Mar. 5-8, Denver, CO)


Electrical and Computer Engineering

Second Department

Mechanical and Aerospace Engineering

Research Center/Lab(s)

Intelligent Systems Center

Second Research Center/Lab

Center for High Performance Computing Research

Keywords and Phrases

Carbon fibers; Fiber optics; Fiber reinforced plastics; Frequency domain analysis; Laminated composites; Natural frequencies; Optical materials; Reflection; Reflectometers; Single mode fibers; Strain gages; Tensile testing; Back-scattered; Distributed sensing; Embedded sensing; Optical Frequency Domain Reflectometry (OFDR); Strain monitoring; Fiber optic sensors; Fiber optic; Rayleigh Backscattered Spectrum (RBS)

International Standard Book Number (ISBN)


International Standard Serial Number (ISSN)

0277-786X; 1996-756X

Document Type

Article - Conference proceedings

Document Version


File Type





© 2018 SPIE, All rights reserved.

Publication Date

01 Mar 2018