Deformation Measurement by a Digital Image Correlation Method Combined with a Hybrid Genetic Algorithm

Digital image correlation (DIC) is a whole-field and non-contact strain measuring method. It could provide deformation information of a specimen by processing two digital images that are captured before and after the deformation. In this work, a hybrid genetic algorithm, in which a simulated annealing mutation process and adaptive mechanisms are added to the real-parameter genetic algorithm, is used to search the corresponding subset after deformation. To invest the accuracy and reliability of this method, some key parameters are considered. The results indicate that the out-of-plane shift should be included, and a subset with 30x30 pixels should be recommended. The population size of 500, 100 generations, and 60 iterations are good enough. As for the searching strategy, it is recommended that the design variables are divided into three groups, each time only one group is under search, and they takes terms consecutively.