Understanding the Working Principle of DIC Technology

The core principle of digital image correlation (DIC) is to measure the deformation and displacement of objects through image comparison. The technique requires applying random black-and-white dots on the object surface; these dots form a specific texture for subsequent image processing. The DIC workflow is usually divided into several steps.

First, before the experiment begins, researchers add texture to the surface of the object to be measured. Then, a high-resolution camera captures the object's initial state to form a reference image. When external force is applied, the object surface deforms, and researchers capture the deformed image again.

Then, the DIC system compares the two images and uses algorithms to identify the displacement of each point. Specifically, DIC matches the small regions (subsets) in the initial image with the deformed image to calculate the displacement and strain of each point. This process is not only efficient but also provides the full-field strain distribution, avoiding the limitations of traditional measurement methods.

The accuracy and real-time capability of DIC make it a preferred method for modern engineering testing. Whether inmaterial mechanics experiments or in structural health monitoring, DIC can provide comprehensive and accurate data support as the basis for engineering decisions.