A novel method for repeatedly generating speckle patterns used in digital image correlation

- Speckle pattern can be controllably generated using an atomization system.
- High repeatability of the desired speckle pattern is achieved.
- Steady performance of Digital Image Correlation (DIC) measurement consistency can be maintained among multiple samples using similar speckle patterns.

Speckle patterns play a key role in Digital Image Correlation (DIC) measurement, and generating an optimal speckle pattern has been the goal for decades now. The usual method of generating a speckle pattern is by manually spraying the paint on the specimen. However, this makes it difficult to reproduce the optimal pattern for maintaining identical testing conditions and achieving consistent DIC results. This study proposed and evaluated a novel method using an atomization system to repeatedly generate speckle patterns. To verify the repeatability of the speckle patterns generated by this system, simulation and experimental studies were systematically performed. The results from both studies showed that the speckle patterns and, accordingly, the DIC measurements become highly accurate and repeatable using the proposed atomization system.