{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,27]],"date-time":"2026-04-27T14:35:13Z","timestamp":1777300513499,"version":"3.51.4"},"reference-count":38,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2018,4,25]],"date-time":"2018-04-25T00:00:00Z","timestamp":1524614400000},"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>In an era of unprecedented progress in sensing technology and communication, health services are now able to closely monitor patients and elderly citizens without jeopardizing their daily routines through health applications on their mobile devices in what is known as e-Health. Within this field, we propose an optical fiber sensor (OFS) based system for the simultaneous monitoring of shear and plantar pressure during gait movement. These parameters are considered to be two key factors in gait analysis that can help in the early diagnosis of multiple anomalies, such as diabetic foot ulcerations or in physical rehabilitation scenarios. The proposed solution is a biaxial OFS based on two in-line fiber Bragg gratings (FBGs), which were inscribed in the same optical fiber and placed individually in two adjacent cavities, forming a small sensing cell. Such design presents a more compact and resilient solution with higher accuracy when compared to the existing electronic systems. The implementation of the proposed elements into an insole is also described, showcasing the compactness of the sensing cells, which can easily be integrated into a non-invasive mobile e-Health solution for continuous remote gait monitoring of patients and elder citizens. The reported results show that the proposed system outperforms existing solutions, in the sense that it is able to dynamically discriminate shear and plantar pressure during gait.<\/jats:p>","DOI":"10.3390\/s18051334","type":"journal-article","created":{"date-parts":[[2018,4,25]],"date-time":"2018-04-25T11:15:39Z","timestamp":1524654939000},"page":"1334","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":57,"title":["Gait Shear and Plantar Pressure Monitoring: A Non-Invasive OFS Based Solution for e-Health Architectures"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3632-757X","authenticated-orcid":false,"given":"C\u00e1tia","family":"Tavares","sequence":"first","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, Aveiro 3810-193, Portugal"},{"name":"Department of Physics &amp; I3N, University of Aveiro, Campus Universit\u00e1rio de Santiago, Aveiro 3810-193, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9958-0409","authenticated-orcid":false,"given":"M. F\u00e1tima","family":"Domingues","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, Aveiro 3810-193, Portugal"},{"name":"CSIC-UPM, Ctra. Campo Real, Arganda del Rey 28500, Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0687-3967","authenticated-orcid":false,"given":"Anselmo","family":"Frizera-Neto","sequence":"additional","affiliation":[{"name":"Telecommunications Laboratory, Electrical Engineering Department, Federal University of Esp\u00edrito Santo, Esp\u00edrito Santo 29075-910, Brazil"}]},{"given":"Tiago","family":"Leite","sequence":"additional","affiliation":[{"name":"Department of Physics &amp; I3N, University of Aveiro, Campus Universit\u00e1rio de Santiago, Aveiro 3810-193, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6331-1215","authenticated-orcid":false,"given":"C\u00e1tia","family":"Leit\u00e3o","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, Aveiro 3810-193, Portugal"},{"name":"Department of Physics &amp; I3N, University of Aveiro, Campus Universit\u00e1rio de Santiago, Aveiro 3810-193, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8176-7953","authenticated-orcid":false,"given":"N\u00e9lia","family":"Alberto","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, Aveiro 3810-193, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8596-5092","authenticated-orcid":false,"given":"Carlos","family":"Marques","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, Aveiro 3810-193, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1935-6077","authenticated-orcid":false,"given":"Ayman","family":"Radwan","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, Aveiro 3810-193, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9618-2176","authenticated-orcid":false,"given":"Eduardo","family":"Rocon","sequence":"additional","affiliation":[{"name":"CSIC-UPM, Ctra. Campo Real, Arganda del Rey 28500, Madrid, Spain"}]},{"given":"Paulo","family":"Andr\u00e9","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering and Instituto de Telecomunica\u00e7\u00f5es, Instituto Superior T\u00e9cnico, University of Lisbon, Lisbon 1049-001, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9129-3539","authenticated-orcid":false,"given":"Paulo","family":"Antunes","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, Campus Universit\u00e1rio de Santiago, Aveiro 3810-193, Portugal"},{"name":"Department of Physics &amp; I3N, University of Aveiro, Campus Universit\u00e1rio de Santiago, Aveiro 3810-193, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,25]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2018, February 13). Aging and Health. 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