{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,7]],"date-time":"2026-01-07T08:01:04Z","timestamp":1767772864387,"version":"build-2065373602"},"reference-count":58,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2019,11,8]],"date-time":"2019-11-08T00:00:00Z","timestamp":1573171200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010665","name":"H2020 Marie Sk\u0142odowska-Curie Actions","doi-asserted-by":"publisher","award":["64215"],"award-info":[{"award-number":["64215"]}],"id":[{"id":"10.13039\/100010665","id-type":"DOI","asserted-by":"publisher"}]},{"name":"H2020-EU.2.1.1.","award":["779411","731667"],"award-info":[{"award-number":["779411","731667"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper addressed the challenge of exploring large, unknown, and unstructured industrial environments with an unmanned aerial vehicle (UAV). The resulting system combined well-known components and techniques with a new manoeuvre to use a low-cost 2D laser to measure a 3D structure. Our approach combined frontier-based exploration, the Lazy Theta* path planner, and a flyby sampling manoeuvre to create a 3D map of large scenarios. One of the novelties of our system is that all the algorithms relied on the multi-resolution of the octomap for the world representation. We used a Hardware-in-the-Loop (HitL) simulation environment to collect accurate measurements of the capability of the open-source system to run online and on-board the UAV in real-time. Our approach is compared to different reference heuristics under this simulation environment showing better performance in regards to the amount of explored space. With the proposed approach, the UAV is able to explore 93% of the search space under 30 min, generating a path without repetition that adjusts to the occupied space covering indoor locations, irregular structures, and suspended obstacles.<\/jats:p>","DOI":"10.3390\/s19224849","type":"journal-article","created":{"date-parts":[[2019,11,8]],"date-time":"2019-11-08T11:30:19Z","timestamp":1573212619000},"page":"4849","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Autonomous 3D Exploration of Large Structures Using an UAV Equipped with a 2D LIDAR"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7812-9969","authenticated-orcid":false,"given":"Margarida","family":"Faria","sequence":"first","affiliation":[{"name":"Robotics, Vision and Control Group, University of Seville, Avda. de los Descubrimientos s\/n, 41092 Sevilla, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3327-9020","authenticated-orcid":false,"given":"Ant\u00f3nio S\u00e9rgio","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Sistemas e Tecnologia Subaqu\u00e1tica (LSTS), Department of Electrical and Computer Engineering, School of Engineering (FEUP), University of Porto, 4200-465 Porto, Portugal"}]},{"given":"H\u00e9ctor","family":"P\u00e9rez-Leon","sequence":"additional","affiliation":[{"name":"Robotics, Vision and Control Group, University of Seville, Avda. de los Descubrimientos s\/n, 41092 Sevilla, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3502-8372","authenticated-orcid":false,"given":"Ivan","family":"Maza","sequence":"additional","affiliation":[{"name":"Robotics, Vision and Control Group, University of Seville, Avda. de los Descubrimientos s\/n, 41092 Sevilla, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4193-9965","authenticated-orcid":false,"given":"Antidio","family":"Viguria","sequence":"additional","affiliation":[{"name":"Center for Advanced Aerospace Technologies, Calle Wilbur y Orville Wright, 19, La Rinconada, 41300 Sevilla, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1555","DOI":"10.1007\/s10514-018-9810-x","article-title":"Advancing multi-vehicle deployments in oceanographic field experiments","volume":"43","author":"Ferreira","year":"2019","journal-title":"Auton. 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