Dem generation based on commercial uav photogrammetry data

Abstract

Unmanned aerial vehicles (UAVs) are used more and more widely in various fields of activity and production. Industries using UAV images include agriculture and land use planning. From the images from the UAV, it is possible to generate digital elevation models (DEM) and digital terrain models (DTM) in a stereophotogrammetric manner, which can be used later for design work. At the same time, there is no need to use expensive specialized UAVs, since budget models of the domestic segment also allow to generate digital terrain models of high accuracy. So, for example, using the PHANTOM 4 model and using certain techniques, it is possible to generate DEM with an error of heights of 5-10 mm. However, such results were obtained due to the creation of almost ideal conditions for aerial survey. The authors of this work were tasked with investigating the possibility of DEM generation of a required accuracy with various options for the location of ground reference points, various parameters of aerial survey provided that photogrammetric processing of images will be carried out in the software Agisoft PhotoScan. To achieve these goals, an object for testing was selected, on which a network of reference and control points was created using a total station. According to the previously calculated parameters, aerial survey was carried out with a PHANTOM 4 UAV. Photogrammetric processing of aerial photographs was carried out in the software Agisoft PhotoScan. The accuracy of digital elevation models was assessed using the least squares method. According to the results of the calculations, the corresponding conclusions are made.