Abstract: This study was based on grating phase-shifting algorithm, a low-cost body measurement experiment system was constructed by digital projector and digital camera. The parallel axis system which can avoid the nonlinear error caused by general crossed- axes system were adapted with projector axis shift and camera local area shooting techniques to expand the effective measurement area, simultaneously the detailed description of the calibration of the system as well as the design principle of the projection grating were given. The four-phase algorithm experiment was carried out for measuring a dummy in this paper, The obtained fringe images were processed and calculated, and unwrapping phases was conducted by a second difference region-growing anti-noise algorithm to avoid the noise, finally, the virtual dummy has been constructed by splicing the front and back cloud data.

Key words: 3-D body measurement, body scanning, phase shifting mehod, projection grating