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A history of the origin and evolution of modal transducers

Technical advances in the past 30 years in digital signal processing, analog to digital converters, computers, and software have resulted in significant gains in the field of experimental modal analysis. Advances in transducer technology (force and acceleration transducers) have also contributed to these gains. The present work first describes the development of the early electromechanical transducers, used to measure force and acceleration, and their associated analog signal conditioning. It then focuses on the technical advances that have occurred in these transducers since the commercialization of the 2-channel digital spectrum analyzers in the beginning 1970s.