Abstract: A model of the surface stress measurement system based on the three-dimensional digital image correlation method is introduced.Two high-speed cameras to synchronously collect the surface image of the tested model and the speckle on the model surface as the carrier is used, the tested model through the image sub-region stereo matching algorithm is matched.Different image sub-regions in the two speckle images before and after the model deformation are solved to obtain the three-dimensional coordinate values of different points on the model, and the three-dimensional deformation information of the model surface is obtained, and the non-contact, dynamic real-time stress measurement of the model surface is realized.

Key words: 3D digital image, Correlation method, Stress measurement, Stereo matching