Land Base and Digital Elevation Model Creation Using Unmanned Aerial Vehicle

Digital elevation model (DEM) layer is most useful for the preparation of water resource applications for creating catchment area and stream order, based on the resolution of DEM the stream order and basin area are changed. Methods behind DEM satellite images, aerial photogrammetry, unmanned aerial vehicle (UAV), GPS, and so on. UAV system is a data collection platform, and as a measurement instrument, UAV gives the high-resolution DEM by the stereopsis principle is becoming attractive for many surveying applications in civil engineering. The present study has investigated the impact of DEM on basin creation and stream order of obtained resolution from UAV of study area at M.V.G.R College Engineering. In this work, a mobile app for capturing aerial images using UAVs, around an area of 63.0 acres, acquired 149 photographs at the 510 ft elevation. Resampled DEM resolution from 5 to 30 m and compared the outputs with the BHUVAN, ASTER, and USGS resolutions. Orthomosaic used as input data set to create the digital layout of study area, DEM as input for water resource applications, and followed the steps  as fill, flow direction, flow accumulation, stream order, and basin by ArcGIS software. The present study created the high-resolution DEM using UAV is 0.325 m and compared with BHUVAN, ASTER, and USGS of resolutions with the help of 20 GPS as checkpoints in the campus at the time of UAV survey. The profile of UAV DEM elevation points is matching with GPS, ASTER, and USGS DEM, except 5 points, and these points are covered with trees within a distance of max 1.5 m. Also, stream order and basins are also affected with resolutions of DEM, and it was compared with 5, 10 20, and 30 m. The stream order was changed from 9 to 4, and basins are changed from 10,359 to 25. High resolution of DEM gives better details compared with medium resolution DEM for small catchment areas. Land base data was prepared with orthoimages of resolution 0.325 m. The significant layers are roads, road median, buildings, playgrounds, poles, trees, water bodies, and seating benches. Finally, it was concluded that UAV applicable to the collection of qualitative data and analysis of collected data.