Three-dimensional shape visualization of object in impact

A method of three-dimensional (3D) shape measurement and visualization of object during impact based on Fourier transform profilometry (FTP) is proposed and verified by experiment. A sequence of dynamic deformed fringe images on the surface of object is grabbed by high speed CCD camera and saved on disk rapidly. Than processed them by Fourier transform, filtering, inverse Fourier transform and unwrapped these phase maps in 3D phase space, the shape deformation of object during impact can be recovered. This method is suitable for wide use in studying such high-speed motion as explosion, expansion, contraction and even shock wave. Based on the phase difference between two neighborhood frames, we propound a 3D phase unwrapping algorithm, which will be of great benefit to 3D phase unwrapping in speed and accuracy. The results of our experiment indicate that the method, presented in this paper, can efficiently deal with the surface shape measurement for rapid motion object and will be a promising one with the development of high-speed frame grabber.