Experimental Mechanics

, Volume 43, Issue 1, pp 61–68 | Cite as

Full-field strain measurement using a luminescent coating

  • James P. Hubner
  • Peter G. Ifju
  • Kirk S. Schanze
  • David A. Jenkins
  • Bruce F. Carroll
  • Yingsheng Wang
  • Phillip He
  • Anthony Brennan
  • Wissam El-Ratal
Article

Abstract

In this paper we describe an optical-based technique, called strain sensitive skin (S3), for measuring in-plane strain data on structural members under static load. The technique employs a coating consisting of a luminescent dye and polymer binder that is applied to the surface of a test part via conventional aerosol techniques. Proper illumination stimulates the dye, which in turn emits higher wavelength luminescence. The excitation and emission intensities have different wavelengths; therefore, enabling optical filtering to separate the two signals. The optical strain response is intensity based. A network of randomized microcracks within the binder scatters the waveguided luminescence from the excited dye molecules. The amount of scattered luminescence is related to the changes in the microcrack openings and orientations via mechanical strain. Various calibration tests show the optical strain response to be proportional to the sum of in-plane principal strains. With this new experimental testing tool, full-field high-resolution strain measurements can be acquired. The optical strain response of this new sensor is minimally dependent on viewing and lighting directions, rendering the technique viable to imaging and determining strain fields for three-dimensional complex geometries.

Key Words

Full-field strain luminescent coating strain-sensitive coating digital imaging 

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Copyright information

© Society for Experimental Mechanics 2003

Authors and Affiliations

  • James P. Hubner
    • 1
  • Peter G. Ifju
    • 1
  • Kirk S. Schanze
    • 2
  • David A. Jenkins
    • 1
  • Bruce F. Carroll
    • 1
  • Yingsheng Wang
    • 2
  • Phillip He
    • 3
  • Anthony Brennan
    • 3
  • Wissam El-Ratal
    • 4
  1. 1.Department of Aerospace Engineering, Mechanics, and Engineering ScienceUniversity of FloridaUSA
  2. 2.Department of ChemistryUniversity of FloridaUSA
  3. 3.Department of Material ScienceUniversity of FloridaUSA
  4. 4.Experimental Engineering Department, Axle/Driveline Systems Engineering, Chassis DivisionVisteon CorporationUSA

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