Frequency-domain modal parameter estimation in the OMAX framework

Abstract

Classical Experimental Modal Analysis (EMA) and Operational Modal Analysis (OMA) were recently combined into the so-called OMAX framework: Operational Modal Analysis with eXogenous inputs. In this framework both the artificial forces and the ambient excitations are considered. The goal of this paper is to present a suitable OMAX procedure in case of structure-exciter interaction. This interaction introduces a correlation between the exciter input force and the unknown ambient excitation. The approach first estimates the frequency response function (FRF), then the (positive) power spectra (XP+) are compensated for the interaction. The parametric estimation of the modal parameters is then identical to the case without interaction.

Publication
Structural Dynamics

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