UNMANNED AERIAL VEHICLE IN CADASTRAL APPLICATIONS

This paper presents the investigation of UAVs (Unmanned Aerial Vehicles) for use in cadastral surveying. Within the scope of a pilot study UAVs were tested for capturing geodata and compared with conventional data acquisition methods for cadastral surveying. Two study sites were therefore surveyed with a tachymeter-GNSS combination as well as a UAV system. The workflows of both methods were investigated and the resulting data were compared with the requirements of Swiss cadastral surveying. Concerning data acquisition and evaluation, the two systems are found to be comparable in terms of time expenditure, accuracy, and completeness. In conclusion, the UAV image orientation proved to be the limiting factor for the obtained accuracy due to the low-cost camera including camera calibration, image quality, and definition of the ground control points (natural or artificial). However, the required level of accuracy for cadastral surveying was reached. The advantage of UAV systems lies in their high flexibility and efficiency in capturing the surface of an area from a low flight altitude. In addition, further information such as orthoimages, elevation models and 3D objects can easily be gained from UAV images. Altogether, this project endorses the benefit of using UAVs in cadastral applications and the new opportunities they provide for cadastral surveying.