{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,25]],"date-time":"2026-02-25T17:40:36Z","timestamp":1772041236983,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,1,18]],"date-time":"2021-01-18T00:00:00Z","timestamp":1610928000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006761","name":"Universidade de Vigo","doi-asserted-by":"publisher","award":[". 00Vl131H 641.02"],"award-info":[{"award-number":[". 00Vl131H 641.02"]}],"id":[{"id":"10.13039\/501100006761","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["EAPA_826\/2018"],"award-info":[{"award-number":["EAPA_826\/2018"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100014440","name":"Ministerio de Ciencia, Innovaci\u00f3n y Universidades","doi-asserted-by":"publisher","award":["PID2019-108816RB-I00"],"award-info":[{"award-number":["PID2019-108816RB-I00"]}],"id":[{"id":"10.13039\/100014440","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Nowadays, unmanned aerial vehicles (UAVs) are extensively used for multiple purposes, such as infrastructure inspections or surveillance. This paper presents a real-time path planning algorithm in indoor environments designed to perform contact inspection tasks using UAVs. The only input used by this algorithm is the point cloud of the building where the UAV is going to navigate. The algorithm is divided into two main parts. The first one is the pre-processing algorithm that processes the point cloud, segmenting it into rooms and discretizing each room. The second part is the path planning algorithm that has to be executed in real time. In this way, all the computational load is in the first step, which is pre-processed, making the path calculation algorithm faster. The method has been tested in different buildings, measuring the execution time for different paths calculations. As can be seen in the results section, the developed algorithm is able to calculate a new path in 8\u20139 milliseconds. The developed algorithm fulfils the execution time restrictions, and it has proven to be reliable for route calculation.<\/jats:p>","DOI":"10.3390\/s21020642","type":"journal-article","created":{"date-parts":[[2021,1,20]],"date-time":"2021-01-20T03:34:25Z","timestamp":1611113665000},"page":"642","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Indoor Path-Planning Algorithm for UAV-Based Contact Inspection"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3898-7854","authenticated-orcid":false,"given":"Luis Miguel","family":"Gonz\u00e1lez de Santos","sequence":"first","affiliation":[{"name":"CINTECX, GeoTECH Group, Campus Universitario de Vigo, University of Vigo, As Lagoas, Marcosende, 36310 Vigo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8626-0545","authenticated-orcid":false,"given":"Ernesto","family":"Fr\u00edas Nores","sequence":"additional","affiliation":[{"name":"CINTECX, GeoTECH Group, Campus Universitario de Vigo, University of Vigo, As Lagoas, Marcosende, 36310 Vigo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0320-4191","authenticated-orcid":false,"given":"Joaqu\u00edn","family":"Mart\u00ednez S\u00e1nchez","sequence":"additional","affiliation":[{"name":"CINTECX, GeoTECH Group, Campus Universitario de Vigo, University of Vigo, As Lagoas, Marcosende, 36310 Vigo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0195-8849","authenticated-orcid":false,"given":"Higinio","family":"Gonz\u00e1lez Jorge","sequence":"additional","affiliation":[{"name":"GeoTECH Group, Department Natural Resources and Environmental Engineering, Campus Lagoas, School of Aerospace Engineering, University of Vigo, 32004 Ourense, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"04019002","DOI":"10.1061\/(ASCE)IS.1943-555X.0000464","article-title":"Applications of UAVs in Civil Infrastructure","volume":"25","author":"Greenwood","year":"2019","journal-title":"J. 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