ABSTRACT
Unpiloted airborne laser scanning (ULS) provides an alternative to traditional airborne laser scanning with piloted aircrafts (ALS). Recent studies showed how the reduction of the size and weight of a laser-scanner facilitated integration of LiDAR on unmanned aerial vehicle platforms allows for a low-altitude flying height providing several times higher point sampling density and survey-grade measurement accuracy in comparison to ALS. Thus, new opportunities emerge to characterise the 3D structure of forests in ways that have not been possible until now. Scanning with a wide range of angles enables resolving individual trees and their branch structure in a similar quality to terrestrial laser scanning. This chapter demonstrates the properties of the data acquired within a case study from western Austria. A mixed forest was scanned from an unpiloted helicopter Scout B1-100 equipped with a VUX-1 LiDAR system. The data provided a high spatial detail for assessing local geomorphology, tree segmentation, and 3D modelling of solar irradiation.
