Analysis of 3D shape and strain distributions of a deformable object using stereo vision

Abstract

This paper proposes a method for analyzing three-dimensional shape and strain distributions of a deformable object using stereo vision. The three-dimensional coordinates of the surface points of an object have been calculated using stereoscopic method. The Fourier transform grid method is applied to high-precision 3D shape and strain distribution of deformable objects by analyzing the phase distribution of grating images. In the conventional automated grid method, because the position of a grid point is expressed by an integer number of pixels, it is difficult to obtain accurate measurement. Using two-dimensional Fourier transform grid method and a two-dimensional cross grating on the surface of the object, we can easily and accrately find the correspondence using phase information and seperate each directional grating line from the two-dimensional grating. Applications for analyzing shape and strain distributions of deformable objects are shown.