Journal of the American Helicopter Society · 1995 · 13 citations · 2 references
EngineeringComputational EngineeringDynamical SystemsStructural AnalysisVibrationDynamic Response AnalysisFrequency ResponseModal AnalysisMode ShapesSpectral AnalysisVibration AnalysisDamped Modal AnalysisDamping EstimationDamping IdentificationFloquet DynamicsModal IdentificationModal Parameter IdentificationState Transition MatrixVibration Mode Analysis
A practical method is proposed to identify the mode associated with the frequency part of the eigenvalue of the Floquet transition matrix (FTM). From the FTM eigenvector, which contains the states and their derivatives, the ratio of the derivative and the state corresponding to the largest component is computed. The method exploits the fact that the imaginary part of this (complex) ratio closely approximates the frequency of the mode. It also lends itself well to automation and has been tested over a large number of FTMs of order as high as 250.
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