{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,24]],"date-time":"2025-11-24T15:09:26Z","timestamp":1763996966518,"version":"3.45.0"},"reference-count":31,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2025,11,23]],"date-time":"2025-11-23T00:00:00Z","timestamp":1763856000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","award":["CTS\/00066","LA\/P\/0104\/2020"],"award-info":[{"award-number":["CTS\/00066","LA\/P\/0104\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study represents a preliminary proof of concept intended to demonstrate the feasibility of using a single-point LiDAR sensor for wearable gait analysis. The study presents a low-cost wearable sensor system that integrates a single-point LiDAR module and IoT connectivity to assess Gait Cycle Duration (GCD) and gait symmetry in real time. The device is positioned on the medial side of the calf to detect the contralateral limb crossing\u2014used as a proxy for mid-stance\u2014enabling the computation of GCD for both limbs and the derivation of the Symmetry Ratio and Symmetry Index. This was conducted under simulated walking at three cadences (slow, normal and fast). GCD estimated by the sensor was compared against the visual annotation with Kinovea\u00ae, showing reasonable agreement, with most cycle-wise relative differences below approximately 13% and both methods capturing similar symmetry trends. The wearable system operated reliably across different speeds, with an estimated materials cost of under 100 \u20ac and wireless data streaming to a cloud dashboard for real-time visualization. Although the validation is preliminary and limited to a single healthy participant and a video-based reference, the results support the feasibility of a photonic, IoT-based approach for portable and objective gait assessment, motivating future studies with larger and clinical cohorts and gold-standard references to quantify accuracy, repeatability and clinical utility.<\/jats:p>","DOI":"10.3390\/s25237148","type":"journal-article","created":{"date-parts":[[2025,11,24]],"date-time":"2025-11-24T14:59:04Z","timestamp":1763996344000},"page":"7148","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Gait Cycle Duration Analysis in Lower Limb Amputees Using an IoT-Based Photonic Wearable Sensor: A Preliminary Proof-of-Concept Study"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-9312-6196","authenticated-orcid":false,"given":"Bruna","family":"Alves","sequence":"first","affiliation":[{"name":"Lisbon School of Engineering (ISEL), Polytechnic University of Lisbon (IPL), 1949-014 Lisboa, Portugal"},{"name":"Escola Superior de Tecnologias da Sa\u00fade de Lisboa, Polytechnic University of Lisbon (IPL), 1990-096 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9938-0351","authenticated-orcid":false,"given":"Alessandro","family":"Fantoni","sequence":"additional","affiliation":[{"name":"Lisbon School of Engineering (ISEL), Polytechnic University of Lisbon (IPL), 1949-014 Lisboa, Portugal"},{"name":"Center of Technology and Systems (UNINOVA-CTS) and Associated Lab of Intelligent Systems (LASI), Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7769-1976","authenticated-orcid":false,"given":"Jos\u00e9 Pedro","family":"Matos","sequence":"additional","affiliation":[{"name":"Escola Superior de Tecnologias da Sa\u00fade de Lisboa, Polytechnic University of Lisbon (IPL), 1990-096 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8058-3685","authenticated-orcid":false,"given":"Jo\u00e3o","family":"Costa","sequence":"additional","affiliation":[{"name":"Lisbon School of Engineering (ISEL), Polytechnic University of Lisbon (IPL), 1949-014 Lisboa, Portugal"},{"name":"Center of Technology and Systems (UNINOVA-CTS) and Associated Lab of Intelligent Systems (LASI), Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1150-9895","authenticated-orcid":false,"given":"Manuela","family":"Vieira","sequence":"additional","affiliation":[{"name":"Lisbon School of Engineering (ISEL), Polytechnic University of Lisbon (IPL), 1949-014 Lisboa, Portugal"},{"name":"Center of Technology and Systems (UNINOVA-CTS) and Associated Lab of Intelligent Systems (LASI), Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal"},{"name":"DEE NOVA School of Science and Technology, New University of Lisbon, Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,23]]},"reference":[{"key":"ref_1","unstructured":"Seymour, R. 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