{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T21:56:34Z","timestamp":1775685394060,"version":"3.50.1"},"reference-count":39,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2021,8,29]],"date-time":"2021-08-29T00:00:00Z","timestamp":1630195200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The increase in flying time of unmanned aerial vehicles (UAV) is a relevant and difficult task for UAV designers. It is especially important in such tasks as monitoring, mapping, or signal retranslation. While the majority of research is concentrated on increasing the battery capacity, it is also important to utilize natural renewable energy sources, such as solar energy, thermals, etc. This article proposed a method for the automatic recognition of cumuliform clouds. Practical application of this method allows diverting of an unmanned aerial vehicle towards the identified cumuliform cloud and improving its probability of flying into a thermal flow, thus increasing the flight time of the UAV, as is performed by glider and paraglider pilots. The proposed method is based on the application of Hough transform and Canny edge detector methods, which have not been used for such a task before. For testing the proposed method a dataset of different clouds was generated and marked by experts. The achieved average accuracy of 87% on the unbalanced dataset demonstrates the practical applicability of the proposed method for detecting thermals related to cumuliform clouds. The article also provides the concept of VilniusTech developed UAV, implementing the proposed method.<\/jats:p>","DOI":"10.3390\/s21175821","type":"journal-article","created":{"date-parts":[[2021,8,31]],"date-time":"2021-08-31T22:58:15Z","timestamp":1630450695000},"page":"5821","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["The Application of Hough Transform and Canny Edge Detector Methods for the Visual Detection of Cumuliform Clouds"],"prefix":"10.3390","volume":"21","author":[{"given":"Aleksandr","family":"Lapu\u0161inskij","sequence":"first","affiliation":[{"name":"Antanas Gustaitis Aviation Institute, Vilnius Gediminas Technical University, LT-08217 Vilnius, Lithuania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ivan","family":"Suzdalev","sequence":"additional","affiliation":[{"name":"Antanas Gustaitis Aviation Institute, Vilnius Gediminas Technical University, LT-08217 Vilnius, Lithuania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2263-3947","authenticated-orcid":false,"given":"Nikolaj","family":"Goranin","sequence":"additional","affiliation":[{"name":"Faculty of Fundamental Sciences, Vilnius Gediminas Technical University, LT-10223 Vilnius, Lithuania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Justinas","family":"Janulevi\u010dius","sequence":"additional","affiliation":[{"name":"Faculty of Fundamental Sciences, Vilnius Gediminas Technical University, LT-10223 Vilnius, Lithuania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3195-4280","authenticated-orcid":false,"given":"Simona","family":"Ramanauskait\u0117","sequence":"additional","affiliation":[{"name":"Faculty of Fundamental Sciences, Vilnius Gediminas Technical University, LT-10223 Vilnius, Lithuania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4718-214X","authenticated-orcid":false,"given":"Gintautas","family":"Stank\u016bnavi\u010dius","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry and Geosciences, Institute of Geosciences of Vilnius University, LT-01513 Vilnius, Lithuania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3","DOI":"10.3846\/16487788.2007.9635955","article-title":"Virtual and flying models for aircraft development","volume":"11","author":"Chiesa","year":"2007","journal-title":"Aviation"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Allen, M. 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