Single-Camera 3D Vibration Detection Based on Combination of Fringe Stripes and Scattered Images

A 3D vibration detection method based on the combination of fringe stripes and scatter patterns is proposed, which uses only a single camera and is capable of acquiring both in-plane and out-of-plane vibrations without any additional optical setup. Firstly, the location of the positioning triangle is detected to lock the stripes to be observed, and the out-of-plane vibration is obtained by calculating the higher-order harmonics generated by the observed stripes; Secondly, the scattering region in the centre of the image is selected where the influence of the out-of-plane vibration can be neglected, and the in-plane vibration is obtained by using digital image correlation method; Lastly, the in-plane vibration is corrected by using the results of the detection of the out-of-plane vibration, and the accurate in-plane vibration is obtained. The proposed method is validated through simulation videos and experiments, and the results show that the proposed method is able to effectively detect three-dimensional vibration with good robustness, indicating that the proposed method has some application prospects in the field of non-contact vibration measurement.