En jämförelse mellan TLS och UAV-fotogrammetri
Inmätning av hårdgjorda ytor
At present day there are several different methods for measuring of paved surfaces.The most common methods today are measuring with a total station, the GlobalNavigation Satellite System (GNSS) and terrestrial laser scanning (TLS). Recently thedevelopment of unmanned aerial vehicles, known as drones, has increasedexponentially and today there are several ways of using drones for measuring surfacesby photographing and laser scanning.This thesis contains a comparison between the methods terrestrial laser scanning(TLS), and unmanned aerial vehicle photogrammetry (UAV). The measurements havebeen applied on two different test surfaces, one of asphalt and one of gravel. Thepurpose of the comparison is to investigate whether the airborne photogrammetry isequivalent accurate in its height levels as the terrestrial laser scanning. For thecomparison to be more extensive, these two methods have not only been comparedin precision but also in the areas of ease of use and economy.The precision was analyzed by comparing the height levels in randomly placed controlpoints on the test surfaces. This has been made possible by the creation of terrainmodels of test surfaces in the software Geo where a surface scan of the models havebeen implemented. With the help of surface control the height deviations in thecontrol points have been calculated and from these deviations the precision of theairborne photogrammetry has been evaluated. The ease of use has been analyzedbased on observations made and information gathered from experienced consultantsfor each technology. For the economic aspect the costs for each measurementmethod has been presented to get an overall picture of each measurement methodcosts.The work has been carried out on behalf of the consulting firm Bjerking AB. The goalis to be able to provide Bjerking with a recommendation for which technology is bestsuited for measuring of paved surfaces.The results of the survey show that the UAV varies by a mean of 11 mm on thesurface of gravel and 2 mm on the surface of the asphalt. The final recommendationgiven is that the UAV is preferred for measurement of asphalt roads, because sincethe precision is equivalent to TLS, the method is safe