Real-Time Vision-Based Modal Parameters Estimation at 10000 fps

In this study, we introduce a real-time vision-based modal parameters estimation system, in which a high-speed vision system operates in real time at 10000 fps for noncontact structural dynamics estimation. The high-speed vision system can extract the displacements of 100 points on a vibrating cantilever beam in 96 x 512 images at 10000 fps by implementing a column-moment calculation circuit logic on a field-programmable logic array. Based on these vibration displacements, the modal parameters of the cantilever beam are simultaneously determined by using an improved output-only modal parameters estimation algorithm. To demonstrate the performance of our 10000-fps vision-based modal parameters estimation system, the resonant frequencies and mode shapes of vibrating steel cantilever beams with artificial damage were estimated in real time.