Digital image correlation with fast Fourier transform for large displacement measurement

Abstract

Digital image correlation is an effective non-contact optical tool for full-field displacement and strain measurements. It is used for objects testing, elastic parameters evaluation, flows control, etc. One of the main challenges of practical realization of DIC is the computation time. In this paper a method of computing digital image correlation with fast Fourier transform algorithm is proposed. Unlike the usual FFT cross correlation algorithm, the proposed method allows for reduction the computation time of large displacements DIC measurements with retaining the accuracy of spatial domain correlation.