An Overview of the Fundamentals of Modal Analysis

Abstract

Modal analysis is an increasingly more important engineering tool that was first applied around 1940 in the search for a better understanding of aircraft dynamic behaviour. Till the end of the 60’s developments were slow and experimental techniques were based on the use of expensive and cumbersome narrow band analogue spectrum analysers. The modern era of modal analysis can be taken as starting at the beginning of the 70’s, based upon the commercial availability of Fast Fourier Transform (FFT) spectrum analysers, transfer function analysers (TFA) and discrete acquisition and analysis of data, together with the availability of increasingly smaller, less expensive and more powerful digital computers to process the data.