柔性曲拱振动测量的双尺度数字图像相关方法OA北大核心CSTPCD

A two-scale digital image correlation method based on flexible curved arch is proposed in this paper.In integer pixel scale,the initial estimation of deformation parameters at pixel level is quickly found by Fourier transform.In sub-pixel scale,combined with pixel level initial estimation and inverse synthesis Gaussian-Newton iteration,the deformation measurement results with sub-pixel precision is obtained.After the vibration response of the structure is obtained,the natural frequency and mode of the structure are identified by frequency domain decomposition method.Finally,the visual measure-ment experiment was conducted on a flexible curved arch,supplemented by comparative analysis of laser vibration measurement,to verify the effectiveness of the proposed method in vibration measurement and modal identification of flexible structures.