Mechanical and Civil Engineering Seminar

Mechanical and Civil Engineering Seminar Series

Title: The "Underestimated" Unseen in Digital Image Correlation: Digital Twin in Material Identification, Full-Field Model Validation and Fracture Mechanics

Abstract: Digital Image Correlation (DIC) is gradually becoming a standard tool in experimental mechanics, for both industry and academia. Despite the fact that the measurement system is often sold with the argument of being easy in use and setup, a poor understanding of issues arising in the whole measurement chain (imaging, noise, correlation algorithm, smoothing, …) can result in poor or misinterpreted results. In this presentation, a digital twin methodology will be presented that relies on the use of synthetic speckle image deformation to generate ground-truth strain images [1], enabling to properly evaluate the spatial resolution and inherent systematic and random errors of DIC. Next, this strategy will be invoked to elaborate on the concept of material testing 2.0 [2] and geometry optimization, applied to composites, elastomers and sheet metal. In a second part, the difficult question of how to validate FEA simulations via full-field DIC data is addressed. The underpinning novelty is the fact that it takes into account the filtering effects of DIC, which according to the authors, is a compulsory step to obtain robust validation [3]. Finally, the digital twin concept will be applied to uncertainty quantification of DIC on fracture properties, such as crack-tip position, crack growth, stress intensity factors and energy release rate using J-Integrals.

Bio: In June 2002 Pascal Lava obtained a master degree in mathematics at Ghent University, followed by a PhD in nuclear physics at Ghent University in 2006. From January 2008 till April 2014, he worked as a professor at the MTM department at Leuven University. He is a co-founder of the spin-off company MatchID, developing optical measurement solutions or Digital Image Correlation (DIC) to assess materials and structures. Currently, he is Managing Director and CTO within MatchID with a specific focus on the integration of DIC with design and development: from the calibration of material models towards the validation of FEA simulations. His personal drive is to improve the general knowledge about DIC and its error sources, increasing the technique's range of credibility and applicability in a plethora of verticals. Pascal is the author of more than 50 peer-reviewed journal papers, a fellow and board member of the International DIC Society and received the SEM A. J. Durelli Award for outstanding contributions to DIC.