TY - GEN

T1 - Load Estimation by Frequency Domain Decomposition

A1 - Pedersen,Ivar Chr. Bjerg

A1 - Hansen,Søren Mosegaard

A1 - Brincker,Rune

A1 - Aenlle,Manuel López

AU - Pedersen,Ivar Chr. Bjerg

AU - Hansen,Søren Mosegaard

AU - Brincker,Rune

AU - Aenlle,Manuel López

PB - Aalborg Universitet

PY - 2007

Y1 - 2007

N2 - When performing operational modal analysis the dynamic loading is unknown, however, once the modal properties of the structure have been estimated, the transfer matrix can be obtained, and the loading can be estimated by inverse filtering. In this paper loads in frequency domain are estimated by analysis of simulated responses of a 4 DOF system, for which the exact modal parameters are known. This estimation approach entails modal identification of the natural eigenfrequencies, mode shapes and damping ratios by the frequency domain decomposition technique. Scaled mode shapes are determined by use of the mass change method. The problem of inverting the often singular or nearly singular transfer function matrix is solved by the singular value decomposition technique using a limited number of singular values. The dependence of the eigenfrequencies on the accuracy of the scaling factors is investigated and the errors on the estimated loads are determined.

AB - When performing operational modal analysis the dynamic loading is unknown, however, once the modal properties of the structure have been estimated, the transfer matrix can be obtained, and the loading can be estimated by inverse filtering. In this paper loads in frequency domain are estimated by analysis of simulated responses of a 4 DOF system, for which the exact modal parameters are known. This estimation approach entails modal identification of the natural eigenfrequencies, mode shapes and damping ratios by the frequency domain decomposition technique. Scaled mode shapes are determined by use of the mass change method. The problem of inverting the often singular or nearly singular transfer function matrix is solved by the singular value decomposition technique using a limited number of singular values. The dependence of the eigenfrequencies on the accuracy of the scaling factors is investigated and the errors on the estimated loads are determined.

SN - 8791606144

VL - Vol. 2

BT - Proceedings of the 2nd International Operational Modal Analysis Conference

T2 - Proceedings of the 2nd International Operational Modal Analysis Conference

A2 - Møller,Nis

ED - Møller,Nis

SP - 669

EP - 676

ER -