ISPRS-Archives The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ISPRS-Archives Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci. 2194-9034 Copernicus Publications Göttingen, Germany 10.5194/isprs-archives-XLIII-B2-2022-1003-2022 COMBINING UNMANNED AERIAL SYSTEMS AND STRUCTURE FROM MOTION PHOTOGRAMMETRY TO RECONSTRUCT THE GEOMETRY OF GROINS Gonçalves D. 1 2 https://orcid.org/0000-0002-9030-3819 Gonçalves G. 1 3 https://orcid.org/0000-0002-1746-0367 Pérez-Alvárez J. 4 Cunha M. C. 2 https://orcid.org/0000-0002-0903-785X Andriolo U. 1 https://orcid.org/0000-0002-0185-7802 INESC Coimbra, Dept. of Electrical and Computer Engineering, Polo 2, 3030-290 Coimbra, Portugal Dept. of Civil Engineering, University of Coimbra, 3030-788 Coimbra, Portugal Dept. of Mathematics, University of Coimbra, 3001-501 Coimbra, Portugal Graphic Expression Dept., University Centre of Merida (CUM), University of Extremadura, 06800 Badajoz, Spain 30 05 2022 XLIII-B2-2022 1003 1008 Copyright: © 2022 D. Gonçalves et al. 2022 This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/ This article is available from https://isprs-archives.copernicus.org/articles/isprs-archives-XLIII-B2-2022-1003-2022.html The full text article is available as a PDF file from https://isprs-archives.copernicus.org/articles/isprs-archives-XLIII-B2-2022-1003-2022.pdf

In the context of coastal environment, the combined use of Unmanned Aerial Systems (UAS) with Structure-from-Motion (SfM) photogrammetry has been demonstrated to be a suitable tool to collect accurate geoinformation. This work aims at investigating the effectiveness of UAS survey to accurately map the geometry of rouble mound groins for monitoring the structural integrity. A set of nadiral images was processed through SfM photogrammetry to obtain the Digital Surface Model (DSM) of the groin. The DSM accuracy was evaluated through the comparison of five profiles measured by the traditional GNSS technique. Overall, vertical accuracy returned a root mean square error of 2.6 cm. The results suggest that UAS combined with SfM photogrammetry can improve the current monitoring of coastal engineering structures by providing high accurate geospatial products.