Analysis of image series through global digital image correlation

A Short Image Series Based Scheme for Time Series Digital Image Correlation

A new scheme for digital image correlation (DIC), i.e., short time series DIC (STS-DIC) is proposed. Instead of processing the original deformed speckle images individually, STS-DIC combines several adjacent deformed speckle images from a short time series and then processes the “averaged image”, for which deformation continuity over time is introduced. The deformation of several adjacent image...

Digital Image Correlation

Comparison of local and global approaches to digital image correlation

Local and global approaches to digital image correlation are compared when the displacement interpolation is based upon bilinear shape functions (i.e., with fournode quadrilaterals). The resolution in terms of displacements and strains associated with both techniques are evaluated a priori and validated a posteriori by using series of images of real experiments. It is shown that global approach...

Full-field bulge testing using global digital image correlation

The miniature bulge test is an acknowledged method for characterizing freestanding thin films. Nevertheless, some discrepancies in the quantitative results from such tests can be found in literature, explained in part by erroneous assumptions in the analytical description used to compute the global stress and strain from the membrane pressure and deflection. In this research, a new method is pr...

Global digital image correlation for pressure deflected membranes

Bulge testing is known for its ability to quantify the mechanical behavior of homogeneous thin membranes. In this method the measured quantities are related to the averaged stress and strain using bulge equations that only exist for a very limited set of membrane geometries. A novel 3D Digital Image Correlation (DIC) method is proposed to directly measure the strain and curvature fields without...