A Compressed Sensing Approach to Operational Modal Analysis Using Phase-Based Video Motion Magnification

Abstract

Phase-based video modal analysis is a modern method of extracting a modal model from a video of a structure’s vibration response. The high spatial resolution inherent to cameras results in high-resolution mode shapes, an obvious advantage in any damage detection application. Unfortunately, the method is limited by the sampling rate of the camera, meaning the high-frequency modes often vital for damage localisation are unobtainable. This paper presents a novel application of compressive sensing to the phase-based video modal analysis method. Compressive sensing allows for signals to be recovered from far fewer samples than traditionally required by the Shannon-Nyquist theorem, thus extending the measurement range of a standard camera.