Areial Land Survey
With the advent of consumer and commercial UAV's or drones, the technology has become something more than just another camera. They have become small portable powerful tools for advanced aerial mapping.
So it all starts with the aircraft. For this article, we flew a DJI Phantom 3 Pro on a pre-defined flight on auto pilot to capture images of a property that met criteria for the ultimate test zone. We wanted to create a flight in an area that would push the limits of the UAV technology and complete a full flight with captured data. Flying a UAV does take a lot of prep no matter what the size is. Pre-flight checks of the subject property and air-craft needed to be completed prior to a full auto pilot programmed flight.
As you can see within the image below, we selected an un developed section of land that bordered two major hydro corridors. The selection of this location was ideal as there was the potential for significant EM interference with the adjacent hydro corridors that would push the limits of the connectivity between the aircraft and the pilot on the ground (which during the entire flight, we did get interference warnings but did not lose connectivity with the aircraft) which the aircraft passed with "flying" colours.
Ground level view of subject property.
After a visual inspection and assessment of the land/property in question a determined flight altitude of 30m would successfully clear all ground obstacles as well as capture a multitude of photography in enough detail so that the output data would exceed any existing aerial imagery and or government data available on current public record.
Once the flight was completed, the images are then downloaded from the aircraft and imported in to software to be analyzed and processed.
Proposed flight plan.
Once the flight was completed, the images are then downloaded from the aircraft and imported in to software to be analyzed and processed.
Collage of all images captured during flight.
Once the flight was completed, the images are then downloaded from the aircraft and imported in to software to be analyzed and processed.
Each image being processed. Each green dot represents a processed image
Initial 2D Outputs
• Nadir orthomosaics in GeoTIFF output format
• Orthomosaics from user-defined orthoplane in GeoTIFF output format
• Google tiles export in .kml and .html output formats
• Index maps (Thermal, DVI, NDVI, SAVI, etc.) in GeoTIFF and GeoJPG format
• Prescription maps in .shp format
Initial 2D Orthomosaic
Initial Digital Surface Model (DSM)
3D Point Cloud
3D point cloud derived from overlapped images gives you the accurate location in the reconstructed object space, displayed in original RGB or classification colors.
Each image taken displayed as thumbnails showing altitude, azimuth an camera tilt angle.
A multitude of outputs after processing can be exported to serve a wide variety users.
• 3D PDF for easy sharing of 3D mesh
• Full 3D textured mesh in .obj, .ply, .dxf, and .fbx format
• Tiled Level-of-detail (LoD) mesh in osgb and slpk (Esri) format
• Point cloud in .las, .laz, .xyz and .ply output format
• Contour lines in .shp, .dxf, .pdf format
• User-defined vector objects in .dxf, .shp, .dgn and .kml format
• Full 3D textured mesh in .obj and .fbx format • Point cloud in .las output format
Below are some 3D models of output files for your use.
Contour model
Contour models can be defined in a multitude of elevations based on resolution captured. Below is a 3D generated contour model at elevation increments of 10cm.
3D Digital Surface Model (DSM) – Un-textured
3D generated models can be used to illustrate any construction proposal by importing the model in to a multitude of softwares and adding in additional 3D geometry of proposed structures
