{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T14:00:22Z","timestamp":1776088822409,"version":"3.50.1"},"reference-count":61,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2017,2,18]],"date-time":"2017-02-18T00:00:00Z","timestamp":1487376000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>UAV Photogrammetry today already enjoys a largely automated and efficient data processing pipeline. However, the goal of dispensing with Ground Control Points looks closer, as dual-frequency GNSS receivers are put on board. This paper reports on the accuracy in object space obtained by GNSS-supported orientation of four photogrammetric blocks, acquired by a senseFly eBee RTK and all flown according to the same flight plan at 80 m above ground over a test field. Differential corrections were sent to the eBee from a nearby ground station. Block orientation has been performed with three software packages: PhotoScan, Pix4D and MicMac. The influence on the checkpoint errors of the precision given to the projection centers has been studied: in most cases, values in Z are critical. Without GCP, the RTK solution consistently achieves a RMSE of about 2\u20133 cm on the horizontal coordinates of checkpoints. In elevation, the RMSE varies from flight to flight, from 2 to 10 cm. Using at least one GCP, with all packages and all test flights, the geocoding accuracy of GNSS-supported orientation is almost as good as that of a traditional GCP orientation in XY and only slightly worse in Z.<\/jats:p>","DOI":"10.3390\/rs9020172","type":"journal-article","created":{"date-parts":[[2017,2,20]],"date-time":"2017-02-20T11:07:24Z","timestamp":1487588844000},"page":"172","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":149,"title":["Testing Accuracy and Repeatability of UAV Blocks Oriented with GNSS-Supported Aerial Triangulation"],"prefix":"10.3390","volume":"9","author":[{"given":"Francesco","family":"Benassi","sequence":"first","affiliation":[{"name":"Department of Engineering and Architecture, University of Parma, Parco Area delle Scienze, 181\/A, 43124 Parma, Italy"}]},{"given":"Elisa","family":"Dall\u2019Asta","sequence":"additional","affiliation":[{"name":"Department of Engineering and Architecture, University of Parma, Parco Area delle Scienze, 181\/A, 43124 Parma, Italy"}]},{"given":"Fabrizio","family":"Diotri","sequence":"additional","affiliation":[{"name":"Environmental Protection Agency of Valle d\u2019Aosta, Climate Change Unit, Loc. Grande Charri\u00e8re, 44, 11020 Saint-Christophe (AO), Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5222-7173","authenticated-orcid":false,"given":"Gianfranco","family":"Forlani","sequence":"additional","affiliation":[{"name":"Department of Engineering and Architecture, University of Parma, Parco Area delle Scienze, 181\/A, 43124 Parma, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4250-9705","authenticated-orcid":false,"given":"Umberto","family":"Morra di Cella","sequence":"additional","affiliation":[{"name":"Environmental Protection Agency of Valle d\u2019Aosta, Climate Change Unit, Loc. Grande Charri\u00e8re, 44, 11020 Saint-Christophe (AO), Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7531-638X","authenticated-orcid":false,"given":"Riccardo","family":"Roncella","sequence":"additional","affiliation":[{"name":"Department of Engineering and Architecture, University of Parma, Parco Area delle Scienze, 181\/A, 43124 Parma, Italy"}]},{"given":"Marina","family":"Santise","sequence":"additional","affiliation":[{"name":"Department of Engineering and Architecture, University of Parma, Parco Area delle Scienze, 181\/A, 43124 Parma, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2017,2,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1671","DOI":"10.3390\/rs4061671","article-title":"Unmanned aircraft systems in remote sensing and scientific research: Classification and considerations of use","volume":"4","author":"Watts","year":"2012","journal-title":"Remote Sens."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1016\/j.isprsjprs.2014.02.013","article-title":"Unmanned aerial systems for photogrammetry and remote sensing: A review","volume":"92","author":"Colomina","year":"2014","journal-title":"ISPRS J. 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