Application of phase shift projection moire technique in solid surfaces topographic survey

The application of projection moire with phase shift techniques in vegetable organs surface topography survey had to step up basic procedures before reaching significant conclusions. As recommended by [1], the proposed method should be tested on virtual surfaces [1] before being carried on solid symmetric surfaces [2], followed by tests on asymmetric surfaces as fruits [3] and finally a generation of a 31) digital models of solid figures as well as of fruits [4]. In this research, identified as the step [2], tested objects included cylinders, cubes and spheres. In this sense a Ronchi grid named G I was generated in a PC, from which other grids referred as G2, G3, and G4 were set out of phase by 1/4, 1/2 and 3/4 of period from G1. Grid G1 was then projected onto the samples surface instead of being virtually distorted, receiving the name of Gd. The difference between Gd and G1, G2, G3, and G4 followed by filtration generated the moire fringes M1,M2, M3 and M4 respectively. Fringes are out of phase one from each other by 114 of period, which were processed by the Rising Sun Moire software to produce packed phase and further on, the unpacked fringes. Final representations in gray levels as well as in contour lines showed the topography of the deformed grid Gd. Parallel line segments were projected onto moire generated surface images to evaluate the approximation to the real surface. Line segments images were then captured by means of the ImageJ software and the corresponding curve fitting obtained. The work conclusions included the reliability of the proposed method in surveying solid figures shape.