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arXiv · 2311.03796

Port-Hamiltonian modeling of multidimensional flexible mechanical structures defined by linear elastic relations $\star$

Abstract

This article presents a systematic methodology for modeling a class of flexible multidimensional mechanical structures defined by linear elastic relations that directly allows to obtain their infinite-dimensional port-Hamiltonian representation. The approach is restricted to systems based on a certain class of kinematic assumptions. However this class encompasses a wide range of models currently available in the literature, such as ${\ell}$-dimensional elasticity models (with ${\ell}$ = 1,2,3), vibrating strings, torsion in circular bars, classical beam and plate models, among others. The methodology is based on Hamilton's principle for a continuum medium which allows defining the energy variables of the port-Hamiltonian system, and also on a generalization of the integration by parts theorem, which allows characterizing the skew-adjoint differential operator and boundary inputs and boundary outputs variables. To illustrate this method, the plate modeling process based on Reddy's third-order shear deformation theory is presented as an example. To the best of our knowledge, this is the first time that an infinite-dimensional port-Hamiltonian representation of this system is presented in the literature.

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Cristobal Ponce, Yongxin Wu, Yann Le Gorrec, Hector Ramirez. 2023-11-07. Port-Hamiltonian modeling of multidimensional flexible mechanical structures defined by linear elastic relations $\star$. https://arxiv.org/abs/2311.03796

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