{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,10]],"date-time":"2026-03-10T18:35:12Z","timestamp":1773167712843,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,5,28]],"date-time":"2021-05-28T00:00:00Z","timestamp":1622160000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004837","name":"Ministerio de Ciencia e Innovaci\u00f3n","doi-asserted-by":"publisher","award":["PRE-2019-087444"],"award-info":[{"award-number":["PRE-2019-087444"]}],"id":[{"id":"10.13039\/501100004837","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004837","name":"Ministerio de Ciencia e Innovaci\u00f3n","doi-asserted-by":"publisher","award":["IJCI-2017-33856"],"award-info":[{"award-number":["IJCI-2017-33856"]}],"id":[{"id":"10.13039\/501100004837","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004837","name":"Ministerio de Ciencia e Innovaci\u00f3n","doi-asserted-by":"publisher","award":["DI-17-09169"],"award-info":[{"award-number":["DI-17-09169"]}],"id":[{"id":"10.13039\/501100004837","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004837","name":"Ministerio de Ciencia e Innovaci\u00f3n","doi-asserted-by":"publisher","award":["IJC2018-035684-I"],"award-info":[{"award-number":["IJC2018-035684-I"]}],"id":[{"id":"10.13039\/501100004837","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Comunidad de Madrid and FEDER Program under grant SINFOTON2-CM","award":["P2018\/NMT-4326"],"award-info":[{"award-number":["P2018\/NMT-4326"]}]},{"name":"European Research Council (OCEAN-DAS)","award":["ERC-2019-POC-875302"],"award-info":[{"award-number":["ERC-2019-POC-875302"]}]},{"name":"Spanish Government","award":["RTI2018-097957-B-C31"],"award-info":[{"award-number":["RTI2018-097957-B-C31"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In recent years, the use of highly flexible wings in aerial vehicles (e.g., aircraft or drones) has been attracting increasing interest, as they are lightweight, which can improve fuel-efficiency and distinct flight performances. Continuous wing monitoring can provide valuable information to prevent fatal failures and optimize aircraft control. In this paper, we demonstrate the capabilities of a distributed optical fiber sensor based on time-expanded phase-sensitive optical time-domain reflectometry (TE-\u03a6OTDR) technology for structural health monitoring of highly flexible wings, including static (i.e., bend and torsion), and dynamic (e.g., vibration) structural deformation. This distributed sensing technology provides a remarkable spatial resolution of 2 cm, with detection and processing bandwidths well under the MHz, arising as a novel, highly efficient monitoring methodology for this kind of structure. Conventional optical fibers were embedded in two highly flexible specimens that represented an aircraft wing, and different bending and twisting movements were detected and quantified with high sensitivity and minimal intrusiveness.<\/jats:p>","DOI":"10.3390\/s21113766","type":"journal-article","created":{"date-parts":[[2021,5,31]],"date-time":"2021-05-31T03:45:29Z","timestamp":1622432729000},"page":"3766","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Monitoring of a Highly Flexible Aircraft Model Wing Using Time-Expanded Phase-Sensitive OTDR"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4819-3898","authenticated-orcid":false,"given":"Miguel","family":"Soriano-Amat","sequence":"first","affiliation":[{"name":"Departamento de Electr\u00f3nica, Universidad de Alcal\u00e1, Alcal\u00e1 de Henares, 28805 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David","family":"Fragas-S\u00e1nchez","sequence":"additional","affiliation":[{"name":"Departamento de Electr\u00f3nica, Universidad de Alcal\u00e1, Alcal\u00e1 de Henares, 28805 Madrid, Spain"},{"name":"Aragon Photonics Labs (APL), C\/Prado 5, 50009 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3927-8125","authenticated-orcid":false,"given":"Hugo F.","family":"Martins","sequence":"additional","affiliation":[{"name":"Instituto de \u00d3ptica, CSIC, 28006 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David","family":"Vallesp\u00edn-Fontcuberta","sequence":"additional","affiliation":[{"name":"R&D Department, ASD Division, Capgemini Engineering, C\/Campezo 1, 28022 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5898-8777","authenticated-orcid":false,"given":"Javier","family":"Preciado-Garbayo","sequence":"additional","affiliation":[{"name":"Aragon Photonics Labs (APL), C\/Prado 5, 50009 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sonia","family":"Martin-Lopez","sequence":"additional","affiliation":[{"name":"Departamento de Electr\u00f3nica, Universidad de Alcal\u00e1, Alcal\u00e1 de Henares, 28805 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miguel","family":"Gonzalez-Herraez","sequence":"additional","affiliation":[{"name":"Departamento de Electr\u00f3nica, Universidad de Alcal\u00e1, Alcal\u00e1 de Henares, 28805 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3561-2405","authenticated-orcid":false,"given":"Mar\u00eda R.","family":"Fern\u00e1ndez-Ruiz","sequence":"additional","affiliation":[{"name":"Departamento de Electr\u00f3nica, Universidad de Alcal\u00e1, Alcal\u00e1 de Henares, 28805 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1647","DOI":"10.1016\/j.engstruct.2004.05.018","article-title":"Recent applications of fiber optic sensors to health monitoring in civil engineering","volume":"26","author":"Li","year":"2004","journal-title":"Eng. 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