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arXiv · 2504.00898

Constitutive relations from images

Adeline Wihardja·Kaushik Bhattacharya
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Abstract

Constitutive relations close the balance laws of continuum mechanics and serves as the surrogate for a material in the design and engineering process. The problem of obtaining the constitutive relations is an indirect inverse problem where both the relation and the quantities that define the relation have to be inferred from experimental observations. The advent of full-field observation techniques promises a new ability of learning constitutive relations in realistic operational conditions. However, this is done in two steps, first obtaining deformations from the images, and then obtaining the constitutive relation from deformations and forces. This leads to a variety of difficulties. In this paper, we propose a novel approach that enables us to obtain constitutive relation directly from the raw data consisting of images and force measurements.

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Adeline Wihardja, Kaushik Bhattacharya. 2025-04-01. Constitutive relations from images. https://arxiv.org/abs/2504.00898

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