Terrestrial Scanning / Archaeology & Cultural Heritage

M. Doneus, M. Pfennigbauer, N. Studnicka, A. Ullrich "Terrestrial Waveform Laser Scanning for Documentation of Cultural Heritage", CIPA 2009 20.09.2009

Due to the fact that terrestrial laser scanning is able to rapidly create a detailed and accurate representation of complex building structures, it is becoming a standard procedure for documentation of cultural heritage. Especially hybrid systems, which combine laser scanning with digital photogrammetry, have become a valuable tool, since they combine the advantages of both photogrammetrical worlds: detailed and accurate recording of surfaces as well as texture plus accurate measurement of edges and corners.
Vegetated areas, however, still pose problems to conventional terrestrial laser scanners. Due to the fact that they only record single range measurements, they are not suitable for recording structures hidden in a forest, or overgrown with different kind of vegetation. A new generation of terrestrial laser scanners based on the pulsed time-of-flight technology could help to solve this problem. They are so called "echo digitization scanners", which are prepared for the online waveform analysis of the entire echo waveform coming back from an emitted single laser pulse. Already during the scanning process, the waveform is processed and multiple echoes discriminated. Therefore, it is possible to detect various objects along the path of the laser beam. Using the last echo and distinguishing between vegetation and solid structures, this technology could help to get better and more detailed information on e.g. buildings within vegetated areas.
Using a case study of a ruined castle, the paper will present the possible implications of this new generation of terrestrial laser scanners for the documentation of cultural heritage.