{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T18:56:12Z","timestamp":1774292172036,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2017,12,16]],"date-time":"2017-12-16T00:00:00Z","timestamp":1513382400000},"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>We propose a novel polymer optical fiber (POF) sensing system based on fiber Bragg gratings (FBGs) to measure foot plantar pressure. The plantar pressure signals are detected by five FBGs, in the same piece of cyclic transparent optical polymer (CYTOP) fiber, which are embedded in a cork insole for the dynamic monitoring of gait. The calibration and measurements performed with the suggested system are presented, and the results obtained demonstrate the accuracy and reliability of the sensing platform to monitor the foot plantar pressure distribution during gait motion and the application of pressure. This architecture does not compromise the patient\u2019s mobility nor interfere in their daily activities. The results using the CYTOP fiber showed a very good response when compared with solutions using silica optical fibers, resulting in a sensitivity almost twice as high, with excellent repeatability and ease of handling. The advantages of POF (e.g., high flexibility and robustness) proved that this is a viable solution for this type of application, since POF\u2019s high fracture toughness enables its application in monitoring patients with higher body mass compared with similar systems based on silica fiber. This study has demonstrated the viability of the proposed system based on POF technology as a useful alternative for plantar pressure detection systems.<\/jats:p>","DOI":"10.3390\/s17122924","type":"journal-article","created":{"date-parts":[[2017,12,19]],"date-time":"2017-12-19T03:54:32Z","timestamp":1513655672000},"page":"2924","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":87,"title":["POFBG-Embedded Cork Insole for Plantar Pressure Monitoring"],"prefix":"10.3390","volume":"17","author":[{"given":"D\u00e9bora","family":"Vilarinho","sequence":"first","affiliation":[{"name":"Department of Physics &amp; I3N, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5912-9138","authenticated-orcid":false,"given":"Antreas","family":"Theodosiou","sequence":"additional","affiliation":[{"name":"Nanophotonics Research Laboratory, Cyprus University of Technology, Limassol 3036, Cyprus"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6331-1215","authenticated-orcid":false,"given":"C\u00e1tia","family":"Leit\u00e3o","sequence":"additional","affiliation":[{"name":"Department of Physics &amp; I3N, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9075-0619","authenticated-orcid":false,"given":"Arnaldo","family":"Leal-Junior","sequence":"additional","affiliation":[{"name":"Telecommunications Laboratory, Electrical Engineering Department, Federal University of Esp\u00edrito Santo, Fernando Ferrari Avenue, Vitoria 29075-910, ES, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9958-0409","authenticated-orcid":false,"given":"Maria","family":"Domingues","sequence":"additional","affiliation":[{"name":"Department of Physics &amp; I3N, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"},{"name":"Centro de Autom\u00e1tica y Rob\u00f3tica, CSIC-UPM, Ctra. Campo Real, Arganda del Rey, 28500 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4541-092X","authenticated-orcid":false,"given":"Kyriacos","family":"Kalli","sequence":"additional","affiliation":[{"name":"Nanophotonics Research Laboratory, Cyprus University of Technology, Limassol 3036, Cyprus"}]},{"given":"Paulo","family":"Andr\u00e9","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es and Department of Electrical and Computer Engineering, Instituto Superior T\u00e9cnico, University of Lisbon, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9129-3539","authenticated-orcid":false,"given":"Paulo","family":"Antunes","sequence":"additional","affiliation":[{"name":"Department of Physics &amp; I3N, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"given":"Carlos","family":"Marques","sequence":"additional","affiliation":[{"name":"Department of Physics &amp; I3N, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2017,12,16]]},"reference":[{"key":"ref_1","unstructured":"Cusano, A., Cutolo, A., and Albert, J. 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