{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T09:28:29Z","timestamp":1777714109468,"version":"3.51.4"},"reference-count":98,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2024,4,30]],"date-time":"2024-04-30T00:00:00Z","timestamp":1714435200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Union\u2019s Horizon 2020 Research and Innovation Programme","doi-asserted-by":"publisher","award":["101021836"],"award-info":[{"award-number":["101021836"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In dynamic and unpredictable environments, the precise localization of first responders and rescuers is crucial for effective incident response. This paper introduces a novel approach leveraging three complementary localization modalities: visual-based, Galileo-based, and inertial-based. Each modality contributes uniquely to the final Fusion tool, facilitating seamless indoor and outdoor localization, offering a robust and accurate localization solution without reliance on pre-existing infrastructure, essential for maintaining responder safety and optimizing operational effectiveness. The visual-based localization method utilizes an RGB camera coupled with a modified implementation of the ORB-SLAM2 method, enabling operation with or without prior area scanning. The Galileo-based localization method employs a lightweight prototype equipped with a high-accuracy GNSS receiver board, tailored to meet the specific needs of first responders. The inertial-based localization method utilizes sensor fusion, primarily leveraging smartphone inertial measurement units, to predict and adjust first responders\u2019 positions incrementally, compensating for the GPS signal attenuation indoors. A comprehensive validation test involving various environmental conditions was carried out to demonstrate the efficacy of the proposed fused localization tool. Our results show that our proposed solution always provides a location regardless of the conditions (indoors, outdoors, etc.), with an overall mean error of 1.73 m.<\/jats:p>","DOI":"10.3390\/s24092864","type":"journal-article","created":{"date-parts":[[2024,4,30]],"date-time":"2024-04-30T08:14:31Z","timestamp":1714464871000},"page":"2864","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Seamless Fusion: Multi-Modal Localization for First Responders in Challenging Environments"],"prefix":"10.3390","volume":"24","author":[{"given":"Dennis","family":"Dahlke","sequence":"first","affiliation":[{"name":"German Aerospace Center (DLR), 12489 Berlin, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3434-3290","authenticated-orcid":false,"given":"Petros","family":"Drakoulis","sequence":"additional","affiliation":[{"name":"Visual Computing Lab, Information Technologies Institute, Centre for Research and Technology Hellas (CERTH), 57001 Thermi, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6102-3121","authenticated-orcid":false,"given":"Anaida","family":"Fern\u00e1ndez Garc\u00eda","sequence":"additional","affiliation":[{"name":"Se\u00f1ales, Sistemas y Radiocomunicaciones, ETSI Telecomunicaci\u00f3n, Universidad Polit\u00e9cnica de Madrid (UPM), 28040 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3210-6259","authenticated-orcid":false,"given":"Susanna","family":"Kaiser","sequence":"additional","affiliation":[{"name":"German Aerospace Center (DLR), 82234 Wessling, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sotiris","family":"Karavarsamis","sequence":"additional","affiliation":[{"name":"Visual Computing Lab, Information Technologies Institute, Centre for Research and Technology Hellas (CERTH), 57001 Thermi, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0237-9555","authenticated-orcid":false,"given":"Michail","family":"Mallis","sequence":"additional","affiliation":[{"name":"Visual Computing Lab, Information Technologies Institute, Centre for Research and Technology Hellas (CERTH), 57001 Thermi, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"William","family":"Oliff","sequence":"additional","affiliation":[{"name":"CS2 Research Centre, School of Computing and Mathematical Sciences, University of Greenwich, London SE10 9LS, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Georgia","family":"Sakellari","sequence":"additional","affiliation":[{"name":"CS2 Research Centre, School of Computing and Mathematical Sciences, University of Greenwich, London SE10 9LS, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4009-2662","authenticated-orcid":false,"given":"Alberto","family":"Belmonte-Hern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Se\u00f1ales, Sistemas y Radiocomunicaciones, ETSI Telecomunicaci\u00f3n, Universidad Polit\u00e9cnica de Madrid (UPM), 28040 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7400-9591","authenticated-orcid":false,"given":"Federico","family":"Alvarez","sequence":"additional","affiliation":[{"name":"Se\u00f1ales, Sistemas y Radiocomunicaciones, ETSI Telecomunicaci\u00f3n, Universidad Polit\u00e9cnica de Madrid (UPM), 28040 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9649-9306","authenticated-orcid":false,"given":"Dimitrios","family":"Zarpalas","sequence":"additional","affiliation":[{"name":"Visual Computing Lab, Information Technologies Institute, Centre for Research and Technology Hellas (CERTH), 57001 Thermi, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,30]]},"reference":[{"key":"ref_1","unstructured":"(2024, February 22). 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