Stereovision measurement of surface deformation of sandwich plates with aluminum foam cores under high speed impact loading

To measure the surface deformation of sandwich plates with aluminum foam cores under high speed impact loading, a stereovision-based surface deformation measurement method was presented. The normalized gray cross-correlation coefficient with the mean value removed was selected to realize area matching. The maximum and minimum parallactic restrictions were acquired by adjusting the disparity range to eliminate the false parallax, and other four constraints were combined with the former to optimize the disparity map. Then 3D point clouds were calculated according to a parallel binocular stereovision model, and the surface deformation profile curves were acquired by using Delaunay triangulation. Moreover, the stereovision 3D measurement system for surface deformation was integrated based on MATLAB, and the precision and comparison experiments for distance measurement were conducted to testify the validity and reliability of the proposed method. The surface deformation 3D measurement test of aluminum foam cores sandwich plates under high speed impact loading was also performed with the integrated system. The results indicate that the reconstructed 3D surface can accurately display the surface deformation of sandwich plates. Accordingly, a brand new approach is achieved to measure surface deformation of target board under high speed impact loading.