High accuracy UAV photogrammetry of ice sheet dynamics with no ground control ...

• Main Authors: Chudley, Thomas R, Christoffersen, Poul, Doyle, Samuel H, Abellan, Antonio, Snooke, Neal
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus GmbH 2018
• Subjects: 37 Earth Sciences; 4013 Geomatic Engineering; 3709 Physical Geography and Environmental Geoscience; 40 Engineering; Ice Sheet
• Online Access: https://dx.doi.org/10.17863/cam.45336; https://www.repository.cam.ac.uk/handle/1810/298281

Abstract. Unmanned Aerial Vehicles (UAVs) and Structure from Motion with Multi-View Stereo (SfM-MVS) photogrammetry are increasingly common tools for geoscience applications, but final product accuracy can be significantly diminished in the absence of a dense and well-distributed network of ground control points (GCPs). This is problematic in inaccessible or hazardous field environments, including highly crevassed glaciers, where implementing suitable GCP networks would be logistically difficult if not impossible. To overcome this challenge, we present an alternative geolocation approach known as GNSS-supported aerial triangulation (GNSS-AT). Here, an on-board carrier-phase GNSS receiver is used to determine the location of photo acquisitions using kinematic differential carrier-phase positioning. The camera positions can be used as the geospatial input to the photogrammetry process. We describe the implementation of this method in a low-cost, custom-built UAV, and apply the method in a glaciological setting ...