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arXiv · 1804.10758

Grey-box state-space identification of nonlinear mechanical vibrations

Jean-Philippe Noël·Johan Schoukens
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Abstract

The present paper deals with the identification of nonlinear mechanical vibrations. A grey-box, or semi-physical, nonlinear state-space representation is introduced, expressing the nonlinear basis functions using a limited number of measured output variables. This representation assumes that the observed nonlinearities are localised in physical space, which is a generic case in mechanics. A two-step identification procedure is derived for the grey-box model parameters, integrating nonlinear subspace initialisation and weighted least-squares optimisation. The complete procedure is applied to an electrical circuit mimicking the behaviour of a single-input, single-output (SISO) nonlinear mechanical system and to a single-input, multiple-output (SIMO) geometrically nonlinear beam structure.

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Jean-Philippe Noël, Johan Schoukens. 2018-04-28. Grey-box state-space identification of nonlinear mechanical vibrations. https://doi.org/10.1080/00207179.2017.1308557

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