Monitoring Shape Change in Compliant Structures

Euan J. Rigg, R. R J Maier, James S. Barton, Andrew J. Moore, J. D C Jones, Scott McCulloch, Andrew Wallwork, Gary Burnell

Research output: Contribution to journalArticle

Abstract

We describe an optical system to monitor small long-term changes in the shape of a surface by using a network of optical fibre Bragg grating strain gauges, for applications in which space does not permit the use of techniques such as photogrammetry or structured light methods. Gratings are bonded to copper beryllium strips held under tension in contact with the test surface. The copper beryllium strips enable sufficient force to be transferred to the optical fibre from the compliant surface. Shape changes are revealed as strain changes in the sensor strips, inferred from wavelength shifts in the Bragg peaks. The optical signals are obtained in reflection by illuminating the sensor fibres with a broadband source and using a scanning Fabry-Perot filter to generate the spectrum with a wavelength resolution of 0.3pm over the range 1530 to 1570nm. Laboratory tests show that a strain resolution of 8 microstrain can be achieved with temperature compensation over the range 20 to 50 C, with a multiplexing capability of between 11 and 16 temperature - strain sensor pairs, depending on temperature gradients on the test surface. We present experimental measurements on a cylindrical test object subject to diametral loading, and show a comparison with a finite element model.

Original languageEnglish
Pages (from-to)206-217
Number of pages12
JournalProceedings of SPIE - the International Society for Optical Engineering
Volume5050
DOIs
Publication statusPublished - 2003
EventPROCEEDINGS OF SPIE SPIE - The International Society for Optical Engineering: Smart Structures and Materials 2003 Smart Sensor Technology and Measurement System - San Diego, CA, United States
Duration: 3 Mar 20035 Mar 2003

Fingerprint

strip
beryllium
sensors
optical fibers
copper
photogrammetry
temperature compensation
strain gages
multiplexing
wavelengths
illuminating
Bragg gratings
optical communication
temperature gradients
gratings
broadband
filters
scanning
fibers
shift

Keywords

  • Compliant structures
  • Fibre Bragg grating
  • Shape change
  • Strain measurement

Cite this

Rigg, Euan J. ; Maier, R. R J ; Barton, James S. ; Moore, Andrew J. ; Jones, J. D C ; McCulloch, Scott ; Wallwork, Andrew ; Burnell, Gary. / Monitoring Shape Change in Compliant Structures. In: Proceedings of SPIE - the International Society for Optical Engineering. 2003 ; Vol. 5050. pp. 206-217.
@article{8a5f10157d3944b1a092baf2b2e30a51,
title = "Monitoring Shape Change in Compliant Structures",
abstract = "We describe an optical system to monitor small long-term changes in the shape of a surface by using a network of optical fibre Bragg grating strain gauges, for applications in which space does not permit the use of techniques such as photogrammetry or structured light methods. Gratings are bonded to copper beryllium strips held under tension in contact with the test surface. The copper beryllium strips enable sufficient force to be transferred to the optical fibre from the compliant surface. Shape changes are revealed as strain changes in the sensor strips, inferred from wavelength shifts in the Bragg peaks. The optical signals are obtained in reflection by illuminating the sensor fibres with a broadband source and using a scanning Fabry-Perot filter to generate the spectrum with a wavelength resolution of 0.3pm over the range 1530 to 1570nm. Laboratory tests show that a strain resolution of 8 microstrain can be achieved with temperature compensation over the range 20 to 50 C, with a multiplexing capability of between 11 and 16 temperature - strain sensor pairs, depending on temperature gradients on the test surface. We present experimental measurements on a cylindrical test object subject to diametral loading, and show a comparison with a finite element model.",
keywords = "Compliant structures, Fibre Bragg grating, Shape change, Strain measurement",
author = "Rigg, {Euan J.} and Maier, {R. R J} and Barton, {James S.} and Moore, {Andrew J.} and Jones, {J. D C} and Scott McCulloch and Andrew Wallwork and Gary Burnell",
year = "2003",
doi = "10.1117/12.484229",
language = "English",
volume = "5050",
pages = "206--217",
journal = "Proceedings of SPIE - the International Society for Optical Engineering",
issn = "1996-756X",
publisher = "SPIE",

}

Monitoring Shape Change in Compliant Structures. / Rigg, Euan J.; Maier, R. R J; Barton, James S.; Moore, Andrew J.; Jones, J. D C; McCulloch, Scott; Wallwork, Andrew; Burnell, Gary.

In: Proceedings of SPIE - the International Society for Optical Engineering, Vol. 5050, 2003, p. 206-217.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Monitoring Shape Change in Compliant Structures

AU - Rigg, Euan J.

AU - Maier, R. R J

AU - Barton, James S.

AU - Moore, Andrew J.

AU - Jones, J. D C

AU - McCulloch, Scott

AU - Wallwork, Andrew

AU - Burnell, Gary

PY - 2003

Y1 - 2003

N2 - We describe an optical system to monitor small long-term changes in the shape of a surface by using a network of optical fibre Bragg grating strain gauges, for applications in which space does not permit the use of techniques such as photogrammetry or structured light methods. Gratings are bonded to copper beryllium strips held under tension in contact with the test surface. The copper beryllium strips enable sufficient force to be transferred to the optical fibre from the compliant surface. Shape changes are revealed as strain changes in the sensor strips, inferred from wavelength shifts in the Bragg peaks. The optical signals are obtained in reflection by illuminating the sensor fibres with a broadband source and using a scanning Fabry-Perot filter to generate the spectrum with a wavelength resolution of 0.3pm over the range 1530 to 1570nm. Laboratory tests show that a strain resolution of 8 microstrain can be achieved with temperature compensation over the range 20 to 50 C, with a multiplexing capability of between 11 and 16 temperature - strain sensor pairs, depending on temperature gradients on the test surface. We present experimental measurements on a cylindrical test object subject to diametral loading, and show a comparison with a finite element model.

AB - We describe an optical system to monitor small long-term changes in the shape of a surface by using a network of optical fibre Bragg grating strain gauges, for applications in which space does not permit the use of techniques such as photogrammetry or structured light methods. Gratings are bonded to copper beryllium strips held under tension in contact with the test surface. The copper beryllium strips enable sufficient force to be transferred to the optical fibre from the compliant surface. Shape changes are revealed as strain changes in the sensor strips, inferred from wavelength shifts in the Bragg peaks. The optical signals are obtained in reflection by illuminating the sensor fibres with a broadband source and using a scanning Fabry-Perot filter to generate the spectrum with a wavelength resolution of 0.3pm over the range 1530 to 1570nm. Laboratory tests show that a strain resolution of 8 microstrain can be achieved with temperature compensation over the range 20 to 50 C, with a multiplexing capability of between 11 and 16 temperature - strain sensor pairs, depending on temperature gradients on the test surface. We present experimental measurements on a cylindrical test object subject to diametral loading, and show a comparison with a finite element model.

KW - Compliant structures

KW - Fibre Bragg grating

KW - Shape change

KW - Strain measurement

UR - http://www.scopus.com/inward/record.url?scp=0242441653&partnerID=8YFLogxK

U2 - 10.1117/12.484229

DO - 10.1117/12.484229

M3 - Article

VL - 5050

SP - 206

EP - 217

JO - Proceedings of SPIE - the International Society for Optical Engineering

JF - Proceedings of SPIE - the International Society for Optical Engineering

SN - 1996-756X

ER -