Digital Image Correlation (DIC) is a powerful method to measure displacement and strain fields, which has become widely used in the experimental mechanics community. While this method is robust and accurate for a variety of applications, standard DIC returns large error and poor correlation quality near displacement discontinuities such as cracks or shear bands. As a result the regions around discontinuities are typically removed from the area of interest, before or after analysis. With subset splitting DIC (SSDIC) the subset is split in two sections when a discontinuity is detected. This method enables the measurement of “displacement jumps”, and also of displacements and strains right by the discontinuity (for example a crack profile or residual strains in the wake can be measured accurately.
Reference: “A Novel Subset Splitting Procedure for Digital Image Correlation on
Discontinuous Displacement Fields” J. Poissant and F. Barthelat.
Experimental Mechanics 50 (3): p. 353-364 (2010) PDF
Comparison of standard DIC and SSDIC for a mode I crack:
The Matlab routines we have developed in this work are available for free.
If you are interested please send an email to firstname.lastname@example.org
mentioning your affiliation and the application you intent for the routines. The package includes:
Standard DIC (1st order subset deformation, quintic interpolation)
Some extra feature: “sequential correlation” option vs. single reference image, strain plotter, filters.