{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,19]],"date-time":"2026-02-19T15:30:22Z","timestamp":1771515022321,"version":"3.50.1"},"reference-count":21,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2021,11,26]],"date-time":"2021-11-26T00:00:00Z","timestamp":1637884800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000024","name":"Canadian Institutes of Health Research","doi-asserted-by":"publisher","award":["FDN - 148450"],"award-info":[{"award-number":["FDN - 148450"]}],"id":[{"id":"10.13039\/501100000024","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Trip-related falls are one of the major causes of injury among seniors in Canada and can be attributable to an inadequate Minimum Toe Clearance (MTC). Currently, motion capture systems are the gold standard for measuring MTC; however, they are expensive and have a restricted operating area. In this paper, a novel wearable system is proposed that can estimate different foot clearance parameters accurately using only two Time-of-Flight (ToF) sensors located at the toe and heel of the shoe. A small-scale preliminary study was conducted to investigate the feasibility of foot clearance estimation using the proposed wearable system. We recruited ten young, healthy females to walk at three self-selected speeds (normal, slow, and fast) while wearing the system. Our data analysis showed an average correlation coefficient of 0.94, 0.94, 0.92 for the normal, slow, and fast speed, respectively, when comparing the ToF signals with motion capture. The ANOVA analysis confirmed these results further by revealing no statistically significant differences between the ToF signals and motion capture data for most of the gait parameters after applying the newly proposed foot angle and offset compensation. In addition, the proposed system can measure the MTC with an average Mean Error (ME) of \u22120.08 \u00b1 3.69 mm, \u22120.12 \u00b1 4.25 mm, and \u22120.10 \u00b1 6.57 mm for normal, slow, and fast walking speeds, respectively. The proposed affordable wearable system has the potential to perform real-time MTC estimation and contribute to future work focused on minimizing tripping risks.<\/jats:p>","DOI":"10.3390\/s21237891","type":"journal-article","created":{"date-parts":[[2021,12,1]],"date-time":"2021-12-01T01:45:02Z","timestamp":1638323102000},"page":"7891","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Design of a Novel Wearable System for Foot Clearance Estimation"],"prefix":"10.3390","volume":"21","author":[{"given":"Shilpa","family":"Jacob","sequence":"first","affiliation":[{"name":"The Kite Research Institute, Toronto Rehabilitation Institute\u2014University Health Network, Toronto, ON M5G 2A2, Canada"},{"name":"Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4821-7650","authenticated-orcid":false,"given":"Geoff","family":"Fernie","sequence":"additional","affiliation":[{"name":"The Kite Research Institute, Toronto Rehabilitation Institute\u2014University Health Network, Toronto, ON M5G 2A2, Canada"},{"name":"Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada"},{"name":"Department of Surgery, University of Toronto, Toronto, ON M5T 1P5, Canada"}]},{"given":"Atena","family":"Roshan Fekr","sequence":"additional","affiliation":[{"name":"The Kite Research Institute, Toronto Rehabilitation Institute\u2014University Health Network, Toronto, ON M5G 2A2, Canada"},{"name":"Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,26]]},"reference":[{"key":"ref_1","unstructured":"Parachute (2021). 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