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arXiv · 2402.01045

LatticeGraphNet: A two-scale graph neural operator for simulating lattice structures

Ayush Jain·Ehsan Haghighat·Sai Nelaturi
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Abstract

This study introduces a two-scale Graph Neural Operator (GNO), namely, LatticeGraphNet (LGN), designed as a surrogate model for costly nonlinear finite-element simulations of three-dimensional latticed parts and structures. LGN has two networks: LGN-i, learning the reduced dynamics of lattices, and LGN-ii, learning the mapping from the reduced representation onto the tetrahedral mesh. LGN can predict deformation for arbitrary lattices, therefore the name operator. Our approach significantly reduces inference time while maintaining high accuracy for unseen simulations, establishing the use of GNOs as efficient surrogate models for evaluating mechanical responses of lattices and structures.

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Ayush Jain, Ehsan Haghighat, Sai Nelaturi. 2024-02-01. LatticeGraphNet: A two-scale graph neural operator for simulating lattice structures. https://doi.org/10.1007/s00366-024-02034-7

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