Basics of Terrestrial Laser Scanning

This chapter introduces the basic concepts of the automatic 3D surveying by means of laser scanning techniques, a methodology developed less than 20 years ago (see, e.g., Boehler et al. 2002) thanks to the technological improvement of the topographical instrumentations, in particular in the movement and in the electronical components. The main topic here explained concerns the geometrical measurement principle of a 3D scene by means of different automatic scans, so performing different 3D point clouds, and the analytical steps to refer such scans to the one chosen coordinate system. Laser scanning technology described in this chapter considers terrestrial static systems, anyway in the last part, some hints are reported about scans acquired by moving systems, as those mounted on aerial vehicles or on portable devices.