ON SITE TIME
Under 30 Minutes
This project served as a benchmarking exercise to validate high-accuracy data acquisition on restricted-access industrial sites. The objective was to generate a survey-grade dataset for stockpile volumetric analysis without requiring physical site access for Ground Control Points (GCPs).
The flight was meticulously planned using DJI FlightHub 2, defining a 1.2km path optimized for consistent overlap and 3D reconstruction.
Operational Flexibility: Operating under an A2 CofC with high-performance, sub-2kg aircraft provides the agility required for the real world. This setup allows us to safely navigate tight industrial boundaries and public or residential areas efficiently, avoiding the restrictive exclusion zones required by GVC or PDRA-01 regulations.
Efficiency: The 33,100sqm area was captured in a single 9-minute flight window, maintaining a steady 2.8m/s to ensure zero motion blur across all 370 images.
To ensure georeferenced integrity without ground-based equipment, the mission utilized Galileo HAS (High Accuracy Service).
Precision without Access: By leveraging Phase 1 Galileo HAS corrections, we achieved enhanced horizontal and vertical positioning directly within the aircraft's metadata.
The Result: This established a validated digital foundation with consistent decimetre-level accuracy. It provides the spatial reliability required for repeatable volumetric measurements—all without the need for traditional RTK base stations or NTRIP corrections.
The results confirm that while a traditional GCP workflow remains the gold standard for projects requiring absolute accuracy, Galileo HAS fundamentally redefines the requirements for rapid deployment. For georeferenced data acquisition on restricted sites, this method delivers the optimal balance of speed and precision—validating it as a reliable alternative when physical site access is constrained.
To achieve the required GSD (Ground Sample Distance) for detailed material analysis, the flight was executed at a constant altitude of 40m.
Data Density: Captured 370 high-resolution images over a 1.2km flight path.
Resolution: Achieved a GSD of 1.08cm/pix, providing the sub-centimetre detail necessary for precise edge-detection in stockpile bases.
Flight Dynamics: A steady velocity of 2.8m/s ensured zero motion blur, critical for high-quality point cloud generation.
The dataset was processed via Agisoft Metashape Professional, using structure-from-motion (SfM) algorithms to reconstruct the site’s complex geometry.
Dense Point Cloud: Generated a high-density 3D skeleton of the site for architectural and engineering reference.
Digital Twin & DSM: Created a survey-grade Digital Surface Model (DSM) used to calculate precise cut-and-fill volumes for bulk aggregate inventory.
Orthomosaic & Contours: Delivered a 1cm resolution site map and topographical contours for ongoing hydrological and site-flow management.
