A modal test is usually required to verify an analytic model used in loads analysis for qualifying aerospace structures. This test defines important structural mode frequencies, mode shapes, and damping and can be performed using any of a number of single and multiple input sine and random excitation methods. Very often, an orthogonality requirement is placed upon the measured modes which implies that very pure modes must be obtained. This need is further complicated when the measured modes, instead of the analytic modes, are used in the loads analysis. An overview of modal test methods and their application to a modal test of a communications satellite provides a comparison of the relative strengths and weaknesses of sine dwell and random excitation techniques.
Comparison of multiple input random and sine excitation methods for aerospace structures
Vergleich zufallsmaessiger mit Mehrfachinput und sinusfoermiger Schwingungsanregungsmethoden fuer Aerospace-Strukturen
Proc. of the 4th Int. Modal Analysis Conf., Union College-Schenectady ; 1 , Feb ; 563-571
1986
8 Seiten, 5 Bilder, 5 Tabellen, 4 Quellen
Conference paper
English
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