Cliff inspection by drone and aerial photogrammetry in Bonifacio
Cliff inspection, September 2018. Results obtained from 370 aerial images taken by the company I-techdrone as part of the restructuring of Bonifacio’s port infrastructure.
Orthophoto and three-dimensional cliff modeling
3D Visualization
As part of the redevelopment of its port infrastructure, the Territorial Collective of Corsica (CTC) engaged the services of the companies I-techdrone and Drones Imaging for the topographic survey of a cliff measuring 400m length and 50m height in Bonifacio.
Using Metashape software, the 370 aerial shots taken by drone allowed to model the cliff in the form of a dense cloud (1pt every 5cm for a high accuracy and restitution of the site’s topography). The 3D model thus generated, whose spatial accuracy is a few centimeters (accuracy obtained thanks to targets previously arranged and measured with a GNSS RTK receiver) allowed the automated export of a hundred topographic sections (cross profiles over the entire length of the cliff) for the detection and location of overhanging areas (immediately identified as risk areas).
Subsequently, this 3D modeling will also serve as initial support to study the morphology of the rock walls and their evolution over time. Indeed, thanks to future aerial surveys and by temporal comparison, it will be possible to locate and quantify automatically the rock walls weakened by erosion and therefore potentially dangerous during the development work of the port.
TECHNICAL INFORMATIONS
- Aerial images processing and analysis service : Drones Imaging.
- Flights and aerial images : I-Techdrone company.
- Spatial accuracy : centimeter.
- Orthophoto RVB : GSD 4mm.
- Total inspected area : 2ha.
- Drone : MikroKopter.
- Photogrammetry software : Agisoft Metashape.
- Export formats : GéoTiff and Las.
- Delivery delay : 2 days.