Fundamentals and applications of optical fiber Bragg grating sensors to textile structural composites

In this paper, a review is given on the principles of optical fiber Bragg grating (FBG) sensors and their applications in textile structural composites (TSCs). As a class of novel all-fiber based components, FBG consists of a spatially periodic modulation in the refractive index along a short length of an optical fiber. FBG sensors are immune to electromagnetic interference, small in size, and easily embedded in a variety of composite materials without compromising the host structures. They can be mass-produced in low cost and are unique in their sensing strategies for absolute wavelength coding and multiplexing. The intrinsic wavelength division multiplexing and localized sensing abilities of FBGs are their most important advantages as they provide an effective means for monitoring physical parameters along a single fiber path. This ability to determine quantitatively internal distributions of physical parameters within a TSC integrated with such sensors has been demonstrated by a number of workers and will lead to a better understanding of the relationship between the structure and physical properties. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.