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Authors
Patrick Guillaume

Identifier
10.3182/20060329-3-AU-2901.00008

Index Terms
modal analysis,vibration,modal parameter estimation,multivariable,aerospace,automotive

Abstract
In this contribution the applicability of frequency-domain estimators in the field of modal analysis will be illustrated. In experimental modal analysis (EMA), mechanical systems with a few inputs and hundreds of outputs have to be identified. This requires adapted frequency-domain estimators designed to handle large amount of data in a reasonable amount of time. Attention will be paid to operational modal analysis, which is a complementary technique to traditional experimental modal analysis. In operational modal analysis unknown operational forces are present. It will be shown how the modal parameters can be estimated from 'output-only' (OMA) as well as 'input/output' (OMAX) measurements done at operating conditions.

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