On accounting for speckle extinction via DIC and PCA

Author(s)

Vargas, R. ^{[1, 2]} ; Canto, R. B. ^{[3, 1]} ; Hild, F. ^[2] ; Roux, S. ^[2]

Affiliation

^[1] Fed Univ Sao Carlos UFSCar, Grad Program Mat Sci & Engn PPGCEM, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Paris Saclay, LMT Lab Mecan & Technol, CNRS, ENS Paris Saclay, F-91190 Gif Sur Yvette - France

^[3] Fed Univ Sao Carlos UFSCar, Dept Mat Engn DEMa, BR-13565905 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: OPTICS AND LASERS IN ENGINEERING; v. 149, FEB 2022.
• Web of Science Citations: 0

Abstract

Digital Image Correlation (DIC) is a full-field measurement technique that generally relies on brightness conservation principles. This work aims to analyze cases in which the speckle pattern vanished after heating, thereby severely altering the brightness. Sets of images acquired during 6 experiments were registered and then used to obtain optimal sets of reference images for each time step via Principal Component Analysis (PCA). The proposed methodology significantly reduced the gray level residuals and provided insight into brightness variations that occurred in the analyzed cases. It was possible to study cases with severe speckle pattern changes by updating the reference image when standard DIC did not converge and using the PCA methodology to obtain optimal reference states. (AU)

• FAPESP's process: 18/15266-0 - Detection and quantification of fracture mechanisms of ceramics at room and high temperatures using digital image correlation
• Grantee: Rodrigo Bresciani Canto
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/23081-0 - Fracture mechanisms of refractories at room and elevated temperatures analyzed with wedge splitting tests and image correlation
• Grantee: Rafael Vargas Maginador
• Support Opportunities: Scholarships in Brazil - Doctorate