Speckle pattern creation methods for two‐dimensional digital image correlation strain measurements applied to mechanical tensile tests up to 700°C

Abstract Background High-resolution Digital Image Correlation (DIC) measurements have previously been produced by stitching of neighboring images, which often requires short working distances. Separately, the image processing community has developed super resolution (SR) imaging techniques, which improve resolution by combining multiple overlapping images. Objective This work investigates the novel pairing of super resolution with digital image correlation, as an alternative method to produce high-resolution full-field strain measurements. Methods First, an image reconstruction test is performed, comparing the ability of three previously published SR algorithms to replicate a high-resolution image. Second, an applied translation is compared against DIC measurement using both low- and super-resolution images. Third, a ring sample is mechanically deformed and DIC strain measurements from low- and super-resolution images are compared. Results SR measurements show improvements compared to low-resolution images, although they do not perfectly replicate the high-resolution image. SR-DIC demonstrates reduced error and improved confidence in measuring rigid body translation when compared to low resolution alternatives, and it also shows improvement in spatial resolution for strain measurements of ring deformation. Conclusions Super resolution imaging can be effectively paired with Digital Image Correlation, offering improved spatial resolution, reduced error, and increased measurement confidence.

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Full-field optical deformation measurement in biomechanics: Digital speckle pattern interferometry and 3D digital image correlation applied to bird beaks

Journal of the Mechanical Behavior of Biomedical Materials ◽

10.1016/j.jmbbm.2012.05.004 ◽

2012 ◽

Vol 14 ◽

pp. 186-191 ◽

Cited By ~ 32

Author(s):

Joris Soons ◽

Pascal Lava ◽

Dimitri Debruyne ◽

Joris Dirckx

Keyword(s):

Digital Image Correlation ◽

Digital Image ◽

Speckle Pattern ◽

Deformation Measurement ◽

Image Correlation ◽

Full Field ◽

Digital Speckle Pattern Interferometry ◽

3D Digital Image Correlation ◽

Digital Speckle

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A Review of Surface Deformation and Strain Measurement Using Two-Dimensional Digital Image Correlation

Metrology and Measurement Systems ◽

10.1515/mms-2016-0028 ◽

2016 ◽

Vol 23 (3) ◽

pp. 461-480 ◽

Cited By ~ 36

Author(s):

Sze-Wei Khoo ◽

Saravanan Karuppanan ◽

Ching-Seong Tan

Keyword(s):

Digital Image Correlation ◽

Digital Image ◽

Strain Measurement ◽

Surface Deformation ◽

Optical Measurement ◽

Image Correlation ◽

Two Dimensional ◽

Full Field ◽

Computation Efficiency ◽

Dimensional Measurements

Abstract Among the full-field optical measurement methods, the Digital Image Correlation (DIC) is one of the techniques which has been given particular attention. Technically, the DIC technique refers to a non-contact strain measurement method that mathematically compares the grey intensity changes of the images captured at two different states: before and after deformation. The measurement can be performed by numerically calculating the displacement of speckles which are deposited on the top of object’s surface. In this paper, the Two-Dimensional Digital Image Correlation (2D-DIC) is presented and its fundamental concepts are discussed. Next, the development of the 2D-DIC algorithms in the past 33 years is reviewed systematically. The improvement of 2DDIC algorithms is presented with respect to two distinct aspects: their computation efficiency and measurement accuracy. Furthermore, analysis of the 2D-DIC accuracy is included, followed by a review of the DIC applications for two-dimensional measurements.

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