{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T11:27:29Z","timestamp":1776338849702,"version":"3.51.2"},"reference-count":46,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,2,1]],"date-time":"2018-02-01T00:00:00Z","timestamp":1517443200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"Natural Science Foundation of China","doi-asserted-by":"publisher","award":["11702175"],"award-info":[{"award-number":["11702175"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31570944"],"award-info":[{"award-number":["31570944"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003453","name":"Natural Science Foundation of Guangdong Province","doi-asserted-by":"publisher","award":["2015A030313553"],"award-info":[{"award-number":["2015A030313553"]}],"id":[{"id":"10.13039\/501100003453","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003453","name":"Natural Science Foundation of Guangdong Province","doi-asserted-by":"publisher","award":["2016A030310068"],"award-info":[{"award-number":["2016A030310068"]}],"id":[{"id":"10.13039\/501100003453","id-type":"DOI","asserted-by":"publisher"}]},{"name":"The Science, Technology and Innovation Committee of Shenzhen City","award":["JCYJ20160422145322758"],"award-info":[{"award-number":["JCYJ20160422145322758"]}]},{"name":"The Science, Technology and Innovation Committee of Shenzhen City","award":["JCYJ20150525092940994"],"award-info":[{"award-number":["JCYJ20150525092940994"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Postural control is a complex skill based on the interaction of dynamic sensorimotor processes, and can be challenging for people with deficits in sensory functions. The foot plantar center of pressure (COP) has often been used for quantitative assessment of postural control. Previously, the foot plantar COP was mainly measured by force plates or complicated and expensive insole-based measurement systems. Although some low-cost instrumented insoles have been developed, their ability to accurately estimate the foot plantar COP trajectory was not robust. In this study, a novel individual-specific nonlinear model was proposed to estimate the foot plantar COP trajectories with an instrumented insole based on low-cost force sensitive resistors (FSRs). The model coefficients were determined by a least square error approximation algorithm. Model validation was carried out by comparing the estimated COP data with the reference data in a variety of postural control assessment tasks. We also compared our data with the COP trajectories estimated by the previously well accepted weighted mean approach. Comparing with the reference measurements, the average root mean square errors of the COP trajectories of both feet were 2.23 mm (\u00b10.64) (left foot) and 2.72 mm (\u00b10.83) (right foot) along the medial\u2013lateral direction, and 9.17 mm (\u00b11.98) (left foot) and 11.19 mm (\u00b12.98) (right foot) along the anterior\u2013posterior direction. The results are superior to those reported in previous relevant studies, and demonstrate that our proposed approach can be used for accurate foot plantar COP trajectory estimation. This study could provide an inexpensive solution to fall risk assessment in home settings or community healthcare center for the elderly. It has the potential to help prevent future falls in the elderly.<\/jats:p>","DOI":"10.3390\/s18020421","type":"journal-article","created":{"date-parts":[[2018,2,2]],"date-time":"2018-02-02T04:20:50Z","timestamp":1517545250000},"page":"421","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Estimation of Foot Plantar Center of Pressure Trajectories with Low-Cost Instrumented Insoles Using an Individual-Specific Nonlinear Model"],"prefix":"10.3390","volume":"18","author":[{"given":"Xinyao","family":"Hu","sequence":"first","affiliation":[{"name":"Institute of Human Factors and Ergonomics, Shenzhen University, Shenzhen 518060, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun","family":"Zhao","sequence":"additional","affiliation":[{"name":"Institute of Human Factors and Ergonomics, Shenzhen University, Shenzhen 518060, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dongsheng","family":"Peng","sequence":"additional","affiliation":[{"name":"Institute of Human Factors and Ergonomics, Shenzhen University, Shenzhen 518060, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8135-1659","authenticated-orcid":false,"given":"Zhenglong","family":"Sun","sequence":"additional","affiliation":[{"name":"Institute of Robotics and Intelligent Manufacturing, the Chinese University of Hong Kong, Shenzhen 518172, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1764-0357","authenticated-orcid":false,"given":"Xingda","family":"Qu","sequence":"additional","affiliation":[{"name":"Institute of Human Factors and Ergonomics, Shenzhen University, Shenzhen 518060, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,2,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"ii7","DOI":"10.1093\/ageing\/afl077","article-title":"Postural orientation and equilibrium: What do we need to know about neural control of balance to prevent falls?","volume":"35","author":"Horak","year":"2006","journal-title":"Age Ageing"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"877","DOI":"10.1016\/0959-4388(94)90137-6","article-title":"Postural control system","volume":"4","author":"Massion","year":"1994","journal-title":"Curr. 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