Deformation Measurement of Scaling and Rotation Objects Based on Digital Image Correlation Method with Color Information

The digital image correlation (DIC) method is widely used in deformation measurement due to the advantages of being non-contact, high precision, full field measurement, and requiring simple experimental equipment. Traditionally, grayscale speckle patterns captured by a monochromatic camera are DIC method. With growing development consumer color cameras, there great potential for developing information This paper proposes scaling- rotation-invariant (SRI-DIC) based on patterns. For integer-pixel matching stage, histogram feature estimate initial value parameters. sub-pixel new error function using three-channel proposed avoid influence illumination changes. In addition, this reverse retrieve strategy instead forward search reduce time. Experiments show that SRI-DIC algorithm not only has scaling rotation invariance, robustness, efficiency, but also average accuracy strain result can reach 0.1%.