{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T19:13:44Z","timestamp":1777490024875,"version":"3.51.4"},"reference-count":40,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,1,29]],"date-time":"2021-01-29T00:00:00Z","timestamp":1611878400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["876659"],"award-info":[{"award-number":["876659"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["876852"],"award-info":[{"award-number":["876852"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011033","name":"Agencia Estatal de Investigaci\u00f3n","doi-asserted-by":"publisher","award":["PCI2020-112240"],"award-info":[{"award-number":["PCI2020-112240"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011033","name":"Agencia Estatal de Investigaci\u00f3n","doi-asserted-by":"publisher","award":["PCI2020-112001"],"award-info":[{"award-number":["PCI2020-112001"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011033","name":"Agencia Estatal de Investigaci\u00f3n","doi-asserted-by":"publisher","award":["EQC2019-006063-P"],"award-info":[{"award-number":["EQC2019-006063-P"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011033","name":"Agencia Estatal de Investigaci\u00f3n","doi-asserted-by":"publisher","award":["RYC-2017-22836"],"award-info":[{"award-number":["RYC-2017-22836"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011698","name":"Junta de Comunidades de Castilla-La Mancha","doi-asserted-by":"publisher","award":["SBPLY\/19\/180501\/000270"],"award-info":[{"award-number":["SBPLY\/19\/180501\/000270"]}],"id":[{"id":"10.13039\/501100011698","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Unmanned aerial vehicles (UAVs) represent a new model of social robots for home care of dependent persons. In this regard, this article introduces a study on people\u2019s feeling of safety and comfort while watching the monitoring trajectory of a quadrotor dedicated to determining their condition. Three main parameters are evaluated: the relative monitoring altitude, the monitoring velocity and the shape of the monitoring path around the person (ellipsoidal or circular). For this purpose, a new trajectory generator based on a state machine, which is successfully implemented and simulated in MATLAB\/Simulink\u00ae, is described. The study is carried out with 37 participants using a virtual reality (VR) platform based on two modules, UAV simulator and VR Visualiser, both communicating through the MQTT protocol. The participants\u2019 preferences have been a high relative monitoring altitude, a high monitoring velocity and a circular path. These choices are a starting point for the design of trustworthy socially assistive UAVs flying in real homes.<\/jats:p>","DOI":"10.3390\/s21030908","type":"journal-article","created":{"date-parts":[[2021,1,29]],"date-time":"2021-01-29T09:25:22Z","timestamp":1611912322000},"page":"908","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Feeling of Safety and Comfort towards a Socially Assistive Unmanned Aerial Vehicle That Monitors People in a Virtual Home"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6094-7197","authenticated-orcid":false,"given":"Lidia M.","family":"Belmonte","sequence":"first","affiliation":[{"name":"Departamento de Ingenier\u00eda El\u00e9ctrica, Electr\u00f3nica, Autom\u00e1tica y Comunicaciones, Universidad de Castilla-La Mancha, 02071 Albacete, Spain"},{"name":"Instituto de Investigaci\u00f3n en Inform\u00e1tica de Albacete, Universidad de Castilla-La Mancha, 02071 Albacete, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0671-324X","authenticated-orcid":false,"given":"Arturo S.","family":"Garc\u00eda","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n en Inform\u00e1tica de Albacete, Universidad de Castilla-La Mancha, 02071 Albacete, Spain"},{"name":"Departamento de Sistemas Inform\u00e1ticos, Universidad de Castilla-La Mancha, 02071 Albacete, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9327-8030","authenticated-orcid":false,"given":"Rafael","family":"Morales","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda El\u00e9ctrica, Electr\u00f3nica, Autom\u00e1tica y Comunicaciones, Universidad de Castilla-La Mancha, 02071 Albacete, Spain"},{"name":"Instituto de Investigaci\u00f3n en Inform\u00e1tica de Albacete, Universidad de Castilla-La Mancha, 02071 Albacete, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1813-398X","authenticated-orcid":false,"given":"Jose Luis","family":"de la Vara","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n en Inform\u00e1tica de Albacete, Universidad de Castilla-La Mancha, 02071 Albacete, Spain"},{"name":"Departamento de Sistemas Inform\u00e1ticos, Universidad de Castilla-La Mancha, 02071 Albacete, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francisco","family":"L\u00f3pez de la Rosa","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n en Inform\u00e1tica de Albacete, Universidad de Castilla-La Mancha, 02071 Albacete, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8211-0398","authenticated-orcid":false,"given":"Antonio","family":"Fern\u00e1ndez-Caballero","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n en Inform\u00e1tica de Albacete, Universidad de Castilla-La Mancha, 02071 Albacete, Spain"},{"name":"Departamento de Sistemas Inform\u00e1ticos, Universidad de Castilla-La Mancha, 02071 Albacete, Spain"},{"name":"Biomedical Research Networking Center in Mental Health (CIBERSAM), 28016 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Nocentini, O., Fiorini, L., Acerbi, G., Sorrentino, A., Mancioppi, G., and Cavallo, F. 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