Path independent stereo digital image correlation with high speed and analysis resolution

Path independent strategy is introduced into stereo digital image correlation, in which high accuracy is attained through the inverse compositional Gauss-Newton (IC-GN) algorithm with the second and the first order shape functions for stereo matching and temporal matching, respectively. To gain strong adaptibility to large and complex deformation or considerable parallax betweent the two views, two robust methods are developped to estimate the initial guess for the iterative IC-GN algorithm. One is aided by scale invariant feature transform (SIFT) features and the other is aided by epipolar constraint. Powered by parallel computing on GPU, the proposed stereo DIC demonstrates high computation efficiency. Real-time stereo DIC is realized and used to measure the large deformation at common video recording rate (similar to 24 fps) with high ananlysis resolution (similar to 6300 points of interest in region of interest).

Automated summary

Path independent strategy is introduced into stereo digital image correlation, achieving high accuracy through the IC-GN algorithm. Two robust methods are developed for initial guess estimation, one using SIFT features and the other aided by epipolar constraint. Real-time stereo DIC is realized with high computation efficiency.