Paper
27 March 2019 Test results of lateral load insensitive FBGs embedded in composites to suppress spectral distortion
Lun-Kai Cheng, Ronald Hagen, Amir Vosteen, Bilim Atli-Veltin, Peter Toet, Freek Molkenboer, Floris van Kempen, Oana van der Togt, Aleksandra Jedynska, Rob Jansen
Author Affiliations +
Abstract
Composite constructions are indispensable in current and future society. Fiber Bragg Gratings (FBGs) embedded in composite need to be carefully aligned with the material fibers to reduce inhomogeneous lateral load exerted onto the FBG which occurs due to the inhomogeneous nature of composite materials. Inhomogeneous load causes distortion of the reflection spectrum. We proposed to solve the FBG spectral distortion by incorporating a dedicated design structure inside the optical fiber. This allows the FBG to sense the strain in the axial direction accurately regardless of the optical fiber alignment with respect to the composite matrix. In this paper, the basic design will be discussed and the results of the first prototype of this structured fiber will be presented. Prototype FBGs are embedded in different composite samples of various thicknesses and materials (glass or carbon fiber based). The spectrum before and after curing is measured and direct comparisons are performed with embedded standard commercial FBG to verify the improvement. Effects of depth of the embedding and FBG direction with respect to the composite material fiber are investigated. Bending and tension tests are performed to ensure the special FBG in the structured fiber has the directional sensitivity to the strain applied. During all experiments, the special FBG is found to have a better or comparable spectrum than the standard FBGs. The improvement varies for the different tests. This can be caused by the unknown orientation of the structure inside the fiber. According to the first FEM analysis, this affects the effectiveness depending on the detail design of the structure. Information of the FEM analysis will be used to further optimize the design and for the development of a prototype.
© (2019) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Lun-Kai Cheng, Ronald Hagen, Amir Vosteen, Bilim Atli-Veltin, Peter Toet, Freek Molkenboer, Floris van Kempen, Oana van der Togt, Aleksandra Jedynska, and Rob Jansen "Test results of lateral load insensitive FBGs embedded in composites to suppress spectral distortion", Proc. SPIE 10970, Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems 2019, 109701Y (27 March 2019); https://doi.org/10.1117/12.2513761
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Fiber Bragg gratings

Composites

Structured optical fibers

Carbon

Distortion

Optical fibers

Manufacturing

Back to Top