Optical Vibration Sensing Technology for Video-Based Behavior Sensing of Structural Objects

This paper introduces an advanced video sensing technology which captures vibration of structural objects, and some efforts to apply it to the deterioration state evaluation of social infrastructure. The technology firstly applies motion tracking to image sequence captured by monocular video camera, and then retrieves minute 3D motions of target objects and in-plane displacements from motion vector fields. The technology finally estimates internal deterioration states based on spatio-temporal behaviors of structures. We have tested the technology in real environments and confirmed that it can successfully retrieve some structural behaviors of hydro turbine bearings and road bridges under external forces.