How and where to use technology of laser scanning and aerial photogrammetry for building purposes - Case study

Abstract

Laser scanning is a method of high - accuracy mapping or reality capture that uses laser beams to quickly capture complete detail of the entire building construction project in a short time. Laser scanners are a great tool for measuring existing buildings but not always because they have the same problem as visual surveys-if you can't see it, you can't scan it, i.e. the laser beam from the scanner can't measure a certain part of the surface of the structure if this part isn't in the scanner's field of view. In particular, this limitation applies to the surfaces of the roof structures and certain parts of the facades. In these cases, the resulting point cloud may contain no information from the building surface what may be a problem for the final results. A possible solution is a combination of two technologies, terrestrial laser scanning and aerial photogrammetry. Aerial photogrammetry (or airborne imagery) means taking of photographs from an unmanned aerial vehicle (i.e. "drones"). The aim of this paper is to describe the use of these two technologies, it means, when it is better to use these technologies separately and when it is better to make their integration. As a reference building the Faculty of Civil Engineering, located in Kosice, Slovakia was chosen.