Acoustic metrology for dimensional conformance

Abstract

This study presents an innovative concept --acoustic metrology--for on-line dimensional conformance inspection. It investigates the linear and radial dimensions as well as the true position of a center. It conclusively finds that as these dimensions change, the resonant frequencies of tested cylindrical and flat plate parts also shift. The high resonant frequencies appear to shift more than low resonant frequencies with linear and radial dimensional deviations of cylindrical parts. However, the dimensional deviations of a flat plate part only influence certain numbers of resonant frequencies. The amount of the frequency changes of all tested parts is proportional to the dimensional deviations. The test results reveal a feasible gaging method that can be used for inspection of a production line for a "Go" or "No Go" decision.