3D modeling by means of videogrammetry and laser scanners for reverse engineering

Abstract

The knowledge of the 3D geometry for reverse engineering studies is based on images and/or distances. The use of scanner laser has replaced the photogrammetry in the last decade, due to its easy handling and intensive data provided. However it requires multiple data captures, a subsequent filtering and a complex data processing, and its accuracy is highly dependent on the material. These limitations mean that many times it will not be the best option (in addition to its high cost). The videogrammetry is capable of generating a high number of images (which implies a high number of points) in a shorter time and regardless of the type of material. This paper analyses the accuracy of a new videogrammetric system respect to two scanner lasers. Results obtained certify that videogrammetry reaches similar accuracy than EScan (high resolution portable 3D scanner for reverse engineering), and higher accuracy than architectural scanner laser. In both cases the time spent in the 3D model generation by means of videogrammetry results much lower and the process is completely automatic requiring no post-processing or filtering work. Finally videogrammetry also enables real 3D object visualization through anaglyphs in all desired positions, while laser systems cannot provide that kind of information.