Experimental Mechanics

, Volume 53, Issue 5, pp 755–765

Diffraction Assisted Image Correlation: A Novel Method for Measuring Three-Dimensional Deformation using Two-Dimensional Digital Image Correlation

Authors

    • Woodruff School of Mechanical EngineeringGeorgia Institute of Technology
  • A. Gdoutou
    • Department of Civil and Environmental EngineeringNorthwestern University
  • G. Ravichandran
    • Graduate Aerospace LaboratoriesCalifornia Institute of Technology
Article

DOI: 10.1007/s11340-012-9687-0

Cite this article as:
Xia, S., Gdoutou, A. & Ravichandran, G. Exp Mech (2013) 53: 755. doi:10.1007/s11340-012-9687-0

Abstract

Digital Image Correlation (DIC) provides a full-field non-contact optical method for accurate deformation measurement of materials, devices and structures. The measurement of three-dimensional (3D) deformation using DIC in general requires imaging with two cameras and a 3D-DIC code. In the present work, a new experimental technique, namely, Diffraction Assisted Image Correlation (DAIC) for 3D displacement measurement using a single camera and 2D-DIC algorithm is presented. A transmission diffraction grating is placed between the specimen and the camera, resulting in multiple images which are then used to obtain apparent in-plane displacements using 2D-DIC. The true in-plane and out-of-plane displacements of the specimen are obtained from the apparent in-plane displacements and the diffraction angle of the grating. The validity and accuracy of the DAIC method are demonstrated through 3D displacement measurement of a small thin membrane. This technique provides new avenues for performing 3D deformation measurements at small length scales and/or dynamic loading conditions.

Keywords

3D digital image correlationDiffractionSmall scaleMembraneDisplacement

Copyright information

© Society for Experimental Mechanics 2012