Marker-Assisted 3D Vibration Visual Measurement with a Single Camera

Vision-based vibration detection technology can realize non-contact detection of global vibration of the structure without affecting the structure, and receives more and more attention in the field of structural health monitoring. Most of the traditional visual vibration measurement techniques can only detect two-dimensional in-plane vibration, while three-dimensional vibration detection requires the assistance of two cameras or optical devices, which makes the utilization of a single camera to achieve three-dimensional vibration detection a pursued goal. In this paper, a marker-assisted 3D vibration detection method is proposed, which requires only a single camera to realize the detection of 3D vibration and has no requirement for the flatness of the surface of the object under test. Out-of-plane vibration detection is achieved by detecting the variation of the distance between two markers in the image, and in-plane vibration detection is achieved by using the variation of the coordinates of the center of the markers. The effectiveness of the proposed method is verified by simulation and experiment, and the results show that the proposed method has certain application prospects.