Identification of structural non-linearities using describing functions and the Sherman-Morrison method

2009-01-01
Ozer, Mehmet Bulent
Özgüven, Hasan Nevzat
Royston, Thomas J.
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In this study, a new method for type and parametric identification of a non-linear element in an otherwise linear structure is introduced. This work is an extension of a previous study in which a method was developed to localize non-linearity in multi-degree of freedom systems and to identify type and parameters of the non-linear element when it is located at a ground connection of the system. The method uses a describing function approach for representing the non-linearity in the structure. The describing function contains only the first harmonic terms. The Sherman-Morrison matrix inversion method is used in the present study to put the response expression in a form where the non-linearity term can be isolated. Using measured responses one can calculate the value of the describing function representation of the non-linear element and thus perform the identification. This new method can be used for type and parametric identification of a non-linear element between any two coordinates of the system. Case studies are given to demonstrate the applicability of the method.
Control and Systems Engineering, Signal Processing, Mechanical Engineering, Civil and Structural Engineering, Aerospace Engineering, Computer Science Applications
https://hdl.handle.net/11511/35483
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
Department of Mechanical Engineering, Article

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Citation Formats
M. B. Ozer, H. N. Özgüven, and T. J. Royston, “Identification of structural non-linearities using describing functions and the Sherman-Morrison method,” MECHANICAL SYSTEMS AND SIGNAL PROCESSING, pp. 30–44, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35483.
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