Simultaneous measurement of dynamic displacement and strain in a single fiber using coarse wavelength-division multiplexing and fiber Bragg-grating filter-based sensing system
Journal
Applied Optics
Journal Volume
55
Journal Issue
9
Start Page
2426
End Page
2434
ISSN
21553165
1559128X
Date Issued
2016
Author(s)
Abstract
Displacement and strain, two of the most important physical quantities in experimental solid mechanics, are seldomly measured simultaneously in a single experimental configuration. In order to provide and improve corresponding sensing techniques, an experimental setup system for simultaneous measurement of dynamic displacement and strain on a flexible cantilever beam using two fiber Bragg gratings (FBGs) in a single fiber is proposed. To realize high-speed multiplexing and demodulation, a configuration incorporating a coarse wavelength-division multiplexing (CWDM) technique and an FBG transmission filter is implemented. The cantilever beam is subjected to steel-ball impact from which the dynamic multipoint displacement/strain sensing performances of the CWDM and FBG filter-based sensing system are demonstrated. Experimental results in temporal and frequency domain are compared with those obtained by the finite element method (FEM) predictions based on identification of the impact-loading history. A noncontact Fotonic displacement sensor and a polyvinylidene-fluoride film (PVDF) strain sensor are also used for comparison. With transient and resonant frequency simulations conducted by the FEM, loading effects of the sensing system are examined. The results obtained in this study indicate that the proposed CWDM and FBG filter-based sensing system is capable of performing simultaneous multipoint displacement/strain measurements in a single fiber with large bandwidth, high sensitivity, and low intensity loss.
Subjects
Bandpass Filters
Bragg Gratings
Cantilever Beams
Displacement Measurement
Dynamics
Fibers
Finite Element Method
Frequency Domain Analysis
Multiplexing
Nanocantilevers
Natural Frequencies
Wavelength Division Multiplexing
Coarse Wavelength Division Multiplexing
Dynamic Displacements
Fiber Bragg Grating Filters
Fiber Bragg Gratings (fbgs)
Flexible Cantilever Beam
Multi-point Displacements
Polyvinylidene Fluoride Films
Simultaneous Measurement
Fiber Bragg Gratings
Publisher
OSA - The Optical Society info@osa.org
Type
journal article