Temporal Aliasing in High-Speed 3-Dimensional Digital Image Correlation Vibration Measurement

Abstract

High-speed 3-dimmensional digital image correlation is rapidly becoming a feasible and practical method for vibration measurement. Despite the growing popularity in dynamic DIC, no known studies focusing on temporal aliasing of a DIC measured vibration response exist. Therefore a study on the potential for and methods to deal with aliasing in vibration measurement utilizing high-speed 3D digital image correlation is conducted. In this study both spatial and temporal aliasing in image processing is addressed. To date it was found that despite there being a wealth of spatial anti-aliasing solutions, they have limited to no impact on aliasing of the DIC displacement time signal used for vibration measurement. No known temporal anti-aliasing technique currently exists for digitized high-speed images for the purposes of motion tracking. Temporal aliasing is therefore likely a pitfall that needs to be systematically avoided during DIC vibration measurement.