UAS RTK / PPK photogrammetry as a tool for mapping the urbanized landscape, creating thematic maps, situation plans and DEM

In contrast to conventional geodetic measurement methods,
photogrammetric methods are often used in combination with RPAS
(Remotely piloted aircraft systems). The result of aerial
photogrammetric measurements is usually an orthophoto map and a
digital elevation model (DEM). In this article, we focused on creating
topographic map data from RPAS aerial photogrammetry in the builtup area, where such maps are missing. Ground control points (GCP)
are standard for georeferencing of photogrammetric measurements.
In our approach, we verified the possibility of mapping completely
without the surveyors entering the area of interest. The quality of
georeferencing the model using RTK / PPK data without GCP was
verified. At checkpoints (CP), average mean errors of 0.031 m in
position and 0.112 m in height were achieved. A DEM, orthophoto
map and point cloud were generated from the photogrammetric
measurements, and surface maps were created from them. The map
data obtained by the two vectorization procedures were compared
using identical points. The difference in position reached the mean
error value of 0.074m, resp. 0.042m compared to the cadastral map.
The result of the whole data processing process are also various other
forms of visualization of the obtained data, e.g. coloured point cloud,
textured 3D mesh surface, terrain slope analysis, etc.