Undersøkelser av GNSS-støttet dronekartlegging

Abstract

With the decrease in price for drones, the last years it has opened up new opportunities for drone mapping. Drones for mapping makes it possible to map with fairy good accuracy. In this thesis, I have studied the result off a mapping drone with RTK. To determine the accuracy I have been using ground control points to test against the point cloud. There have also been a subjective evaluation of the point cloud, regarding the buildings, vegetation and tarmac. The results without any GCP was descent in x and y. As expected was the height more wrong then the ground plan. This is because of that the drone and GPS to measure the GCP used RTK/CPOS. As we know, RTK/CPOS is less accurate in the height then ground plan. At first sight, the point cloud looks good. When going in detail the flaws appears. The walls of buildings is often not that great or even sometimes missing. Trees without leaves is often only the trunks. Pine trees is often good. The vegetation need to be thick to be able to become modeled. The orthophoto had to be adjusted some places. It was often the corners of the buildings that had malformations. Aerial mapping with a drone works fine to map large areas without high accuracy.