Digital Mapping (“DEM”, “DSM”,”DTM”)
A Digital Elevation Model (DEM) is a continuous 3D representation of a terrain surface area that has been geometrically corrected, so it can be used to measure distances and heights. Two main kinds of DEM can be generated:
- Digital Terrain Model (DTM): 3D representation of the terrain base surface without vegetation and artificial objects.
- Digital Surface Model (DSM): 3D representation of all elements in the area.
The UAV flight can generate a DTM in every flight as a product of the rectification process “(orthophotos)”. From this previous DTM, with more intensive software procedures, a low resolution “Point Cloud” 3D model can be generated, from which a high-resolution DSM can be derived.
Digital Elevation Model Applications
Acquiring in the same flight an orthophoto plus a DEM, provides a high quality and low-.cost product than can be used to support any topography and cartography & GIS work. With further processing, medium density Cloud Point and DSM can also be obtained, which leads to applications in multiple fields:
- Civils works
- Forestry and Environmental
- Resolutions accuracy of approximately 10cm/pixel (depending upon acquisition height)
- Can capture relatively large areas per flight
- Can be delivered to work with industry standard GIS software
- Fast post processing time and final output from UAV capture
- When combined with Ground Control Points can overlay existing datasets
Rapid cost effective digital modelling, fast, efficient and accurate..