実験モード解析における級数展開を用いた剰余項設定の提案

概要

論文の詳細を見る
In the experimental modal analysis, correct expression of the frequency response function (FRF) is indispensable for obtaining precise modal parameters by curve fitting. The FRF of a system of multiple degrees of freedom is explained as a summation of The FRF of systems of a single degree of freedom. In this explanation, only the natural modes within the object limits of frequency are adopted, and all natural modes of lower and higher frequency domain are neglected. The error caused by this neglection is revised with the residual terms. The usual residual terms are formulated of two constants called the inertial restraint and the residual compliance. But the revision of the error is not sufficient with these usual terms. A new formulation of the residual terms is proposed in the present paper by the series expansion of the FRF. Namely, FRFs of the lower and the higher frequency domains are expanded by Laurent and Taylor expansion methods, respectively. It is confirmed using both a model and an actual car body, that the proposed residual terms yield more precise modal parameters than the conventional ones.
1990-05-25