Modal Parameter Estimation for Underdamped Linear Dynamic Systems

Abstract:

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.

• Periodical: Applied Mechanics and Materials (Volume 486)
• Pages: 233-238
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.486.233
• Online since: December 2013
• Authors: Fillemon Nduvu Nangolo*
• Keywords: Damping, Modal Parameter, Natural Frequency, Vibration

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