A Self Adaptive Global Digital Image Correlation Algorithm

A novel Digital Image Correlation algorithm is presented, focussing on accurately determining small strains with high strain gradients. Principles from p-adaptive finite element analysis are implemented to obtain a self adapting higher order mesh. The self adapting principle reduces the dependency of the results on the user’s input and the higher orders insure sufficient degrees of freedom. Performance of the algorithm, in terms of resolution and spatial resolution, is checked and compared to the traditional local method. The results indicate that the introduced method is appropriate for accurately measuring high heterogeneous deformations and that the obtained data is to a large extent user independent.