Pit Digital Twin: How PhotoMesh and TerraExplorer Calculate Stripping and Stockpile Volumes from Drone Data

A mine's survey team typically calculates stripping, waste dump, and stockpile volumes from field survey data — a total station, or less often a terrestrial laser scanner. The method itself isn't the problem; its frequency is. The pit keeps changing between surveys, so by the time a report reaches the chief engineer's desk, some of the numbers are already outdated.

Drone photogrammetry addresses exactly this gap — not replacing legally binding surveyor boundary measurements, but closing the interval between them with weekly, or even daily, volume checks.

From a set of photos to a 3D pit model

PhotoMesh automatically builds a photo-realistic 3D model from a series of drone images — no manual stitching or manual ground control point tie-in required. The output is a dense point cloud and 3D mesh accurate enough for close-range volumetric surveying.

TerraBuilder merges the results of multiple flights — along with satellite imagery and existing terrain models — into a single georeferenced terrain database. That matters for pits surveyed in sections (different pit walls and dumps on different days) or where new data needs to line up with historical terrain.

Volume tracking in TerraExplorer

The finished model opens in TerraExplorer Desktop, where the volume measurement tool compares the current surface against the previous survey or the design model, returning the difference in cubic meters of stripping, waste, or remaining reserves. The same model checks slope angles, berm widths, and how actual mining progress matches the design plan.

Through SkylineGlobe Server, the result is published for the whole team — from the pit foreman to the planning department — without installing desktop software on every workstation.

What this changes for the operation

• Survey frequency. A monthly geodetic survey becomes a weekly or daily drone flight with automated volume recalculation.
• Earlier warning signs. Deviations between actual volumes and the mine plan become visible within weeks, not at the end of a reporting period.
• One model, several teams. The same 3D pit model serves surveyors tracking volumes, safety teams monitoring wall stability, and management for planning and presentations.

Conclusion

Drone photogrammetry doesn't replace traditional surveying, but it fundamentally changes how often you can check. The PhotoMesh → TerraBuilder → TerraExplorer pipeline turns a routine drone flight over the pit into a data source for weekly, not monthly, volume control — at the accuracy industrial reporting requires.

KEG TRK is Skyline Software's partner in Kazakhstan. We'll help configure PhotoMesh and TerraExplorer for a specific pit, dump, or production site. Get in touch to discuss implementation.