UAV photogrammetry for topographic monitoring of coastal areas

• Tipo: Artigo em Revista Científica Internacional
• Data: 2015

Autores

Jose A Goncalves (Autor) FCUP; Henriques, R (Autor) Outra

Revista

Título: ISPRS Journal of Photogrammetry and Remote Sensing

Vol. 104

Páginas: 101-111

ISSN: 0924-2716

Editora: Elsevier

Indexação

ISI Web of Knowledge - 387 Citações

Scopus - 470 Citações

Outras Informações

ID Authenticus: P-00A-99F

DOI: 10.1016/j.isprsjprs.2015.02.009

Abstract (EN): Coastal areas suffer degradation due to the action of the sea and other natural and human-induced causes. Topographical changes in beaches and sand dunes need to be assessed, both after severe events and on a regular basis, to build models that can predict the evolution of these natural environments. This is an important application for airborne LIDAR, and conventional photogrammetry is also being used for regular monitoring programs of sensitive coastal areas. This paper analyses the use of unmanned aerial vehicles (UAV) to map and monitor sand dunes and beaches. A very light plane (SwingletCam) equipped with a very cheap, non-metric camera was used to acquire images with ground resolutions better than 5 cm. The Agisoft Photoscan software was used to orientate the images, extract point clouds, build a digital surface model and produce orthoimage mosaics. The processing, which includes automatic aerial triangulation with camera calibration and subsequent model generation, was mostly automated. To achieve the best positional accuracy for the whole process, signalised ground control points were surveyed with a differential GPS receiver. Two very sensitive test areas on the Portuguese northwest coast were analysed. Detailed DSMs were obtained with 10 cm grid spacing and vertical accuracy (RMS) ranging from 3.5 to 5.0 cm, which is very similar to the image ground resolution (3.2-4.5 cm). Where possible to assess, the planimetric accuracy of the orthoimage mosaics was found to be subpixel. Within the regular coastal monitoring programme being carried out in the region, UAVs can replace many of the conventional flights, with considerable gains in the cost of the data acquisition and without any loss in the quality of topographic and aerial imagery data.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 11