In this graduation thesis heights gathered from GNSS levelling are being compared with heights from
digital surface model (DSM), made with an unmanned aerial vehicle. The measurements took place in
the Vače village. Points in the field were measured with the real time kinematic method of GNSS
levelling. At the same time an unmanned aerial vehicle, owned by Geavis d. o. o. company, flew over
the area and took photographs of it. Using their software they made a digital surface model, which we
used for camparison. They also created an ortophoto to help us recognize points on site. Measured
points were divided into three classes: road, mowed grassfield and unmowed grassfield. From
compared heights of the same points, acquired from GNSS and DSM, for each class differences in
heights were computed. They exceeded the possible accuracy of RTK-method of GNSS-levelling,
with smallest differences at the mowed grassfield and biggest at the unmowed ones. Based on our
results we suggest caution when using DSM height data from unmanned aerial vehicle, especially in
the areas with high vegetation.
|
