Experimental modal analysis using a tracking interferometer

Experimental modal analysis is carried out for machine tools and in various other industries. It is used for dynamic characterization, diagnostics, condition monitoring, design optimization and as comparison data for computation results. 3D-scanning laser Doppler velocimeters and three-axial accelerometers dominate the experimental modal analysis today. This paper presents a method for modal analysis using a tracking interferometer as well for geometric measurement as for simultaneous 3D-vibration measurement with a single laser beam. A holistic measurement procedure is developed, its performance and robustness against external influences is investigated and a benchmark against accelerometers is carried out at a machining center.