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arXiv · 1610.09145

Grey-box nonlinear state-space modelling for mechanical vibrations identification

Jean-Philippe Noël·Johan Schoukens·Gaetan Kerschen
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Abstract

In the present paper, a flexible and parsimonious model of the vibrations of nonlinear mechanical systems is introduced in the form of state-space equations. It is shown that the nonlinear model terms can be formed using a limited number of output measurements. A two-step identification procedure is derived for this grey-box model, integrating nonlinear subspace initialisation and maximum likelihood optimisation. The complete procedure is demonstrated on the Silverbox benchmark, which is an electrical mimicry of a single-degree-of-freedom mechanical system with one displacement-dependent nonlinearity.

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Jean-Philippe Noël, Johan Schoukens, Gaetan Kerschen. 2016-10-28. Grey-box nonlinear state-space modelling for mechanical vibrations identification. https://doi.org/10.1016/j.ifacol.2015.12.230

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