An Intensity-Based Demodulation Approach for the Measurement of Strains Induced by Structural Vibrations using Bragg Gratings

Abstract

The Structural Irregularity and Damage Evaluation Routine (SIDER) is a broadband vibration-based technique that uses features in the complex curvature operating shapes of vibrating structures to locate damage and other areas with structural stiffness variations. Historically SIDER has determined these shapes using out-of-plane acceleration measurements, however it may also be possible to determine these complex curvature operating shapes by using arrays of fibre Bragg gratings to measure the dynamic strain profile of the vibrating structure. This report outlines a review of commercially available FBG demodulation systems with the requirements of SIDER in mind. Three commercially available systems were assessed in the Laboratory and found to be unsuitable for this study. Hence in order to achieve a suitable outcome a purpose-built demodulation system was developed by DSTO. This report describes the assessment of the commercial systems as well as the development and evaluation of the DSTO purpose-built demodulation system.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Feb 01, 2011
Accession Number
ADA538086

Entities

People

  • C. E. Davis
  • P. E. Norman

Organizations

  • Defence Science and Technology Group

Tags

Communities of Interest

  • Materials and Manufacturing Processes
  • Sensors

DTIC Thesaurus Topics

  • Analyzers
  • Bragg Gratings
  • Calibration
  • Communications Protocols
  • Composite Structures
  • Detection
  • Detectors
  • Dynamic Response
  • Engineering
  • Fiber Bragg Gratings
  • Frequency Analyzers
  • Measurement
  • Optical Fibers
  • Resonant Frequency
  • Shape
  • Test And Evaluation
  • Trailing Edges

Fields of Study

  • Physics

Readers

  • Facility/Structural Engineering.
  • Optical Fiber Sensing and Electromagnetic Propagation.
  • Systems Analysis and Design