Modal Parameter Estimation in Multi-Patch Operational Modal Analysis: Perspectives and Approaches

Modal parameter estimation is the estimation of frequency, damping ratio, and modal coefficients from experimental data. Modal analysis techniques are a common method used to determine these properties. The Least-Squares Complex Exponential (LSCE) and the Eigensystem Realization Algorithm (ERA) are one of the popular methods of modal analysis techniques. This paper presents an experimental verification of the LSCE and ERA methods. The investigation focuses on the estimation of natural frequencies, damping ratio and modal coefficients. To investigate this, artificial analytical data were processed in MATLAB environment to estimate the modal parameters. The identified vibration parameters from the LSCE and ERA were compared with the values based on classical dynamic theory, and the natural frequency and damping ratios percent of error were calculated.

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Stochastic subspace identification for output-only modal analysis: accuracy and sensitivity on modal parameter estimation

10.1117/12.876619 ◽

2011 ◽

Cited By ~ 2

Author(s):

Yi-Cheng Liu ◽

Chin-Hsiung Loh

Keyword(s):

Parameter Estimation ◽

Modal Analysis ◽

Subspace Identification ◽

Modal Parameter ◽

Stochastic Subspace Identification ◽

Output Only ◽

Modal Parameter Estimation

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Experimental modal analysis in research

Budownictwo i Architektura ◽

10.24358/bud-arch_17_163_01 ◽

2017 ◽

Vol 16 (3) ◽

pp. 005-012 ◽

Cited By ~ 1

Author(s):

Mariusz Żółtowski ◽

Krzysztof Napieraj

Keyword(s):

Parameter Estimation ◽

Modal Analysis ◽

Civil Engineering ◽

Experimental Modal Analysis ◽

Impact Testing ◽

Engineering Industry ◽

Vibration Modes ◽

Modal Parameter ◽

Excitation Techniques ◽

Modal Parameter Estimation

Experimental modal analysis has grown steadily in popularity since the advent of the digital FFT spectrum analyser in the 1970’s. This days impact testing has become widespread as a fast and economical means of finding the vibration modes of a machine or structure. Its significantly use ascending roles can be seen also in the civil engineering industry [6]. This paper reviews the main topics associated with experimental modal analysis including making FRF measurements, modal excitation techniques, and modal parameter estimation from a set of FRFs.

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Second-Order Blind Identification for Operational Modal Analysis

Volume 1: 21st Biennial Conference on Mechanical Vibration and Noise, Parts A, B, and C ◽

10.1115/detc2007-34480 ◽

2007 ◽

Cited By ~ 6

Author(s):

F. Poncelet ◽

G. Kerschen ◽

J. C. Golinval ◽

F. Marin

Keyword(s):

Modal Analysis ◽

Operational Modal Analysis ◽

Blind Identification ◽

Modal Parameter ◽

Engineering Structures ◽

Experimental Application ◽

Large Structures ◽

Output Only ◽

Modal Parameter Estimation ◽

Source Signals

For modal analysis of large structures, it is unpractical and expensive to use artificial excitation (e.g., shakers). However, engineering structures are most often subject to ambient loads (e.g., traffic and wind) that can be exploited for modal parameter estimation. One difficulty is that the actual loading conditions cannot generally be measured, and output-only measurements are available. This paper proposes to explore the utility of blind source separation (BSS) techniques for operational modal analysis. The basic idea of BSS is to recover unobserved source signals from their observed mixtures. The feasibility and practicality of the proposed method are demonstrated using an experimental application.

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