{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T03:46:24Z","timestamp":1768275984731,"version":"3.49.0"},"reference-count":37,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2021,9,15]],"date-time":"2021-09-15T00:00:00Z","timestamp":1631664000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004663","name":"Ministry of Science and Technology, Taiwan","doi-asserted-by":"publisher","award":["MOST 110-2221-E-224-050"],"award-info":[{"award-number":["MOST 110-2221-E-224-050"]}],"id":[{"id":"10.13039\/501100004663","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Multirotor unmanned aerial vehicles (MUAVs) are becoming more prominent for diverse real-world applications due to their inherent hovering ability, swift manoeuvring and vertical take-off landing capabilities. Nonetheless, to be entirely applicable for various obstacle prone environments, the conventional MUAVs may not be able to change their configuration depending on the available space and perform designated missions. It necessitates the morphing phenomenon of MUAVS, wherein it can alter their geometric structure autonomously. This article presents the development of a morphed MUAV based on a simple rotary actuation mechanism capable of driving each arm\u2019s smoothly and satisfying the necessary reduction in workspace volume to navigate in the obstacle prone regions. The mathematical modelling for the folding mechanism was formulated, and corresponding kinematic analysis was performed to understand the synchronous motion characteristics of the arms during the folding of arms. Experiments were conducted by precisely actuating the servo motors based on the proximity ultrasonic sensor data to avoid the obstacle for achieving effective morphing of MUAV. The flight tests were conducted to estimate the endurance and attain a change in morphology of MUAV from \u201cX-Configuration\u201d to \u201cH-Configuration\u201d with the four arms actuated synchronously without time delay.<\/jats:p>","DOI":"10.3390\/s21186192","type":"journal-article","created":{"date-parts":[[2021,9,15]],"date-time":"2021-09-15T12:00:44Z","timestamp":1631707244000},"page":"6192","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Design and Implementation of Morphed Multi-Rotor Vehicles with Real-Time Obstacle Detection and Sensing System"],"prefix":"10.3390","volume":"21","author":[{"given":"Aleligne Yohannes","family":"Shiferaw","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Centre for Autonomous System Research, Vel Tech Rangarajan Dr Sagunthala R & D Institute of Science and Technology, Avadi, Chennai 600062, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4663-4132","authenticated-orcid":false,"given":"Balasubramanian","family":"Esakki","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Centre for Autonomous System Research, Vel Tech Rangarajan Dr Sagunthala R & D Institute of Science and Technology, Avadi, Chennai 600062, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tamilarasan","family":"Pari","sequence":"additional","affiliation":[{"name":"Department of Aeronautical Engineering, Centre for Autonomous System Research, Vel Tech Rangarajan Dr Sagunthala R & D Institute of Science and Technology, Avadi, Chennai 600062, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elangovan","family":"Elumalai","sequence":"additional","affiliation":[{"name":"Department of Electronics and Communication Engineering, Centre for Autonomous System Research, Vel Tech Rangarajan Dr Sagunthala R & D Institute of Science and Technology, Avadi, Chennai 600062, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5676-1875","authenticated-orcid":false,"given":"Saleh","family":"Mobayen","sequence":"additional","affiliation":[{"name":"Future Technology Research Center, National Yunlin University of Science and Technology, 123 University Road, Section 3, Douliou 64002, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1271-8488","authenticated-orcid":false,"given":"Andrzej","family":"Bartoszewicz","sequence":"additional","affiliation":[{"name":"Institute of Automatic Control, Lodz University of Technology, 18\/22 Stefanowskiego St., 90-924 Lodz, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,15]]},"reference":[{"key":"ref_1","first-page":"460","article-title":"Science, technology and the future of small autonomous drones","volume":"521","author":"Floreano","year":"2015","journal-title":"Nat. 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