{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T14:33:40Z","timestamp":1785335620093,"version":"3.55.0"},"reference-count":44,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,3,18]],"date-time":"2022-03-18T00:00:00Z","timestamp":1647561600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FEDER\/Ministerio de Ciencia e Innovaci\u00f3n\u2014Agencia Estatal de Investigaci\u00f3n. Spain","award":["Proyect RTI2018-101897-B-I00"],"award-info":[{"award-number":["Proyect RTI2018-101897-B-I00"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, we aim to open up new perspectives in the field of autonomous aerial surveillance and target tracking systems, by exploring an alternative that, surprisingly, and to the best of the authors\u2019 knowledge, has not been addressed in that context by the research community thus far. It can be summarized by the following two questions. Under the scope of such applications, what are the implications and possibilities offered by mounting several steerable cameras onboard of each aerial agent? Second, how can optimization algorithms benefit from this new framework, in their attempt to provide more efficient and cost-effective solutions on these areas? The paper presents the idea as an additional degree of freedom to be exploited, which can enable more efficient alternatives in the deployment of such applications. As an initial approach, the problem of the optimal positioning with respect to a set of targets of one single agent, equipped with several onboard tracking cameras with different or variable focal lengths, is addressed. As a consequence of this allowed heterogeneity in focal lengths, the notion of distance needs to be adapted into a notion of optical range, as the agent can trade longer Euclidean distances for correspondingly longer focal lengths. Moreover, the proposed optimization indices try to balance, in an optimal way, the verticality of the viewpoints along with the optical range to the targets. Under these premises, several positioning strategies are proposed and comparatively evaluated.<\/jats:p>","DOI":"10.3390\/s22062359","type":"journal-article","created":{"date-parts":[[2022,3,20]],"date-time":"2022-03-20T21:37:17Z","timestamp":1647812237000},"page":"2359","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Flying Chameleons: A New Concept for Minimum-Deployment, Multiple-Target Tracking Drones"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8504-0575","authenticated-orcid":false,"given":"Manuel","family":"Vargas","sequence":"first","affiliation":[{"name":"Department of Automation and Systems Engineering, University of Seville, Camino de los Descubrimientos s\/n, 41092 Seville, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3211-2731","authenticated-orcid":false,"given":"Carlos","family":"Vivas","sequence":"additional","affiliation":[{"name":"Department of Automation and Systems Engineering, University of Seville, Camino de los Descubrimientos s\/n, 41092 Seville, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0494-6533","authenticated-orcid":false,"given":"Francisco R.","family":"Rubio","sequence":"additional","affiliation":[{"name":"Department of Automation and Systems Engineering, University of Seville, Camino de los Descubrimientos s\/n, 41092 Seville, Spain"},{"name":"Laboratory of Engineering for Energy and Environmental Sustainability, University of Seville, Camino de los Descubrimientos s\/n, 41092 Seville, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5463-2455","authenticated-orcid":false,"given":"Manuel G.","family":"Ortega","sequence":"additional","affiliation":[{"name":"Department of Automation and Systems Engineering, University of Seville, Camino de los Descubrimientos s\/n, 41092 Seville, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1541","DOI":"10.1109\/JPROC.2011.2158377","article-title":"Eyes in the sky: Decentralized control for the deployment of robotic camera networks","volume":"99","author":"Schwager","year":"2011","journal-title":"Proc. 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