TU Darmstadt / ULB / TUbiblio

Neural networks meet hyperelasticity: a guide to enforcing physics

Linden, Lennart ; Klein, Dominik K. ; Kalina, Karl A. ; Brummund, Jörg ; Weeger, Oliver ; Kästner, Markus (2023)
Neural networks meet hyperelasticity: a guide to enforcing physics.
In: Journal of the Mechanics and Physics of Solids
doi: 10.1016/j.jmps.2023.105363
Artikel, Bibliographie

Kurzbeschreibung (Abstract)

In the present work, a hyperelastic constitutive model based on neural networks is proposed which fulfills all common constitutive conditions by construction, and in particular, is applicable to compressible material behavior. Using different sets of invariants as inputs, a hyperelastic potential is formulated as a convex neural network, thus fulfilling symmetry of the stress tensor, objectivity, material symmetry, polyconvexity, and thermodynamic consistency. In addition, a physically sensible stress behavior of the model is ensured by using analytical growth terms, as well as normalization terms which ensure the undeformed state to be stress free and with zero energy. In particular, polyconvex, invariant-based stress normalization terms are formulated for both isotropic and transversely isotropic material behavior. By fulfilling all of these conditions in an exact way, the proposed physics-augmented model combines a sound mechanical basis with the extraordinary flexibility that neural networks offer. Thus, it harmonizes the theory of hyperelasticity developed in the last decades with the up-to-date techniques of machine learning. Furthermore, the non-negativity of the hyperelastic neural network-based potentials is numerically examined by sampling the space of admissible deformations states, which, to the best of the authors’ knowledge, is the only possibility for the considered nonlinear compressible models. For the isotropic neural network model, the sampling space required for that is reduced by analytical considerations. In addition, a proof for the non-negativity of the compressible Neo-Hooke potential is presented. The applicability of the model is demonstrated by calibrating it on data generated with analytical potentials, which is followed by an application of the model to finite element simulations. In addition, an adaption of the model to noisy data is shown and its extrapolation capability is compared to models with reduced physical background. Within all numerical examples, excellent and physically meaningful predictions have been achieved with the proposed physics-augmented neural network.

Typ des Eintrags: Artikel
Erschienen: 2023
Autor(en): Linden, Lennart ; Klein, Dominik K. ; Kalina, Karl A. ; Brummund, Jörg ; Weeger, Oliver ; Kästner, Markus
Art des Eintrags: Bibliographie
Titel: Neural networks meet hyperelasticity: a guide to enforcing physics
Sprache: Englisch
Publikationsjahr: 26 Juni 2023
Verlag: Elsevier
Titel der Zeitschrift, Zeitung oder Schriftenreihe: Journal of the Mechanics and Physics of Solids
DOI: 10.1016/j.jmps.2023.105363
URL / URN: https://www.sciencedirect.com/science/article/abs/pii/S00225...
Kurzbeschreibung (Abstract):

In the present work, a hyperelastic constitutive model based on neural networks is proposed which fulfills all common constitutive conditions by construction, and in particular, is applicable to compressible material behavior. Using different sets of invariants as inputs, a hyperelastic potential is formulated as a convex neural network, thus fulfilling symmetry of the stress tensor, objectivity, material symmetry, polyconvexity, and thermodynamic consistency. In addition, a physically sensible stress behavior of the model is ensured by using analytical growth terms, as well as normalization terms which ensure the undeformed state to be stress free and with zero energy. In particular, polyconvex, invariant-based stress normalization terms are formulated for both isotropic and transversely isotropic material behavior. By fulfilling all of these conditions in an exact way, the proposed physics-augmented model combines a sound mechanical basis with the extraordinary flexibility that neural networks offer. Thus, it harmonizes the theory of hyperelasticity developed in the last decades with the up-to-date techniques of machine learning. Furthermore, the non-negativity of the hyperelastic neural network-based potentials is numerically examined by sampling the space of admissible deformations states, which, to the best of the authors’ knowledge, is the only possibility for the considered nonlinear compressible models. For the isotropic neural network model, the sampling space required for that is reduced by analytical considerations. In addition, a proof for the non-negativity of the compressible Neo-Hooke potential is presented. The applicability of the model is demonstrated by calibrating it on data generated with analytical potentials, which is followed by an application of the model to finite element simulations. In addition, an adaption of the model to noisy data is shown and its extrapolation capability is compared to models with reduced physical background. Within all numerical examples, excellent and physically meaningful predictions have been achieved with the proposed physics-augmented neural network.

Zusätzliche Informationen:

Artikel-ID: 105363

Fachbereich(e)/-gebiet(e): 16 Fachbereich Maschinenbau
16 Fachbereich Maschinenbau > Fachgebiet Cyber-Physische Simulation (CPS)
Hinterlegungsdatum: 03 Jul 2023 09:04
Letzte Änderung: 03 Jul 2023 09:04
PPN:
Export:
Suche nach Titel in: TUfind oder in Google
Frage zum Eintrag Frage zum Eintrag

Optionen (nur für Redakteure)
Redaktionelle Details anzeigen Redaktionelle Details anzeigen