Drone topographic survey

Surveying tens or hundreds of hectares with GNSS RTK and a total station alone can take weeks. Drone photogrammetry covers the same area with dense data in one or two days: the height of every point is computed from overlapping images, so the terrain is described in a level of detail that ground methods cannot match. The method is especially efficient for land plots, residential developments, industrial zones and road or pipeline corridors.

Before the flight, ground control points are placed on site and measured with GNSS RTK; with RTK/PPK drones their number can be reduced, but check points are always kept. Flight height is chosen for the required scale, usually giving a ground pixel size of 1.5–3 cm. Processing produces a point cloud, vegetation and buildings are filtered out to obtain a bare-earth model, and contours are drawn at 0.5–1 m intervals.

Buildings, roads, fences, poles, manholes and other features are digitised from the orthophoto. Elements not visible in the imagery, such as manhole depths, ground under trees or building corners, are measured additionally with GNSS RTK and a total station. The final topographic plan is delivered in AutoCAD/Civil 3D format in the national coordinate system.

When you need it

• Topographic base for designing large land plots
• Planning residential developments and industrial zones
• Road, canal and pipeline corridor surveys
• Agricultural and land reclamation projects
• Surveying hard-to-reach or hazardous areas

What's included

• GNSS RTK measurement of ground control and check points
• Flight planning and aerial imaging
• Photogrammetric processing and point cloud generation
• Digital terrain model and contours
• Digitising features from the orthophoto
• Ground measurement of features not visible from the air

How we work

1. Agreeing site limits, scale and accuracy
2. Preparing flight permits and flight plan
3. Measuring control points and flying
4. Photogrammetric processing and accuracy check
5. Preparing the topographic plan and handover

Deliverables

• Topographic plan (DWG, PDF)
• Digital terrain model and contours
• Orthophoto (GeoTIFF)
• Accuracy report on check points