Introduction to Drone & UAV Mapping
Drones equipped with cameras enable high-resolution, on-demand geospatial data collection at centimeter-level accuracy.
Theory & Foundations
UAVs capture overlapping photographs that are processed through Structure from Motion (SfM) photogrammetry to create orthomosaics, DSMs, and 3D models.
Fixed-wing drones: Longer flight time (60–90 min), larger coverage (500+ hectares/flight), but need runway. Ideal for agricultural monitoring and corridor mapping.
Multi-rotor drones: Hover capability, vertical takeoff, smaller areas (50–100 hectares), but shorter flights (20–35 min). Perfect for construction, inspection, and urban mapping.
Common sensors: RGB cameras (standard photography), multispectral (5-band for vegetation analysis), thermal (heat detection for energy/agriculture), LiDAR (3D point clouds through vegetation).
Flight parameters: Ground Sample Distance (GSD) = altitude × sensor_pixel_size / focal_length. Higher altitude = larger GSD = lower resolution. Typical overlap: 75% frontal, 65% lateral.
In-Depth Coverage
Drone Types
Platform selection depends on mission requirements.
- Multi-rotor (DJI Mavic/Phantom): Easy to fly, hover, inspect
- Fixed-wing (senseFly eBee): Large area mapping, long endurance
- VTOL (WingtraOne): Combines hover takeoff with fixed-wing efficiency
- Heavy-lift: Carry LiDAR, large-format cameras
Deliverables
Drone processing produces multiple geospatial products.
- Orthomosaic: Geometrically corrected aerial photo mosaic
- DSM/DTM: Digital Surface/Terrain Model for elevation
- 3D Point Cloud: Dense points with XYZ + RGB values
- 3D Mesh: Textured surface model for visualization
- Contour lines: Topographic contours from elevation data
Regulations
Drone operations require compliance with national aviation rules.
- Bangladesh CAAB: Registration, pilot license, flight permits
- USA FAA Part 107: Remote pilot certificate, <400ft AGL
- EU: Open/Specific/Certified categories by risk
- No-fly zones: Airports, military, restricted airspace
Key Techniques
Data Visualization
- Multi-rotor: 70%
- Fixed-wing: 20%
- VTOL: 8%
- Heavy-lift: 2%
- 📋PlanMission planning, GSD, overlap settings
- 🛩️FlyAutomated flight with image capture
- ⚙️ProcessSfM alignment, dense cloud, mesh
- 🗺️DeliverOrthomosaic, DSM, 3D model, contours
Practical Workflow
- Define project requirements and accuracy
- Check airspace regulations and get permits
- Plan flight: altitude, overlap, GSD target
- Deploy GCPs with RTK-GPS coordinates
- Execute flight with automated mission
- Transfer and inspect imagery
- Process in SfM software
- Export deliverables: orthomosaic, DSM, 3D model
Software & Tools
Video Tutorials
Real-World Application
Real-World Projects
Drone surveys of Mahasthangarh archaeological site at 2cm resolution.
Case Study
Problem-Based Learning
Construction firm needs 5cm contour lines for earthwork volume calculation.
Solution: Fly drone at 80m AGL (2cm GSD), 80% overlap, deploy 8 GCPs with RTK. Process in Pix4D. Generate DTM and contour lines.