{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,21]],"date-time":"2026-03-21T13:31:30Z","timestamp":1774099890002,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2021,9,6]],"date-time":"2021-09-06T00:00:00Z","timestamp":1630886400000},"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":["51767006"],"award-info":[{"award-number":["51767006"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004479","name":"Natural Science Foundation of Jiangxi Province","doi-asserted-by":"publisher","award":["20202ACBL214021, 20202BAB202005"],"award-info":[{"award-number":["20202ACBL214021, 20202BAB202005"]}],"id":[{"id":"10.13039\/501100004479","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013064","name":"Key Research and Development Plan of Jiangxi Province","doi-asserted-by":"publisher","award":["20202BBGL73098"],"award-info":[{"award-number":["20202BBGL73098"]}],"id":[{"id":"10.13039\/501100013064","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Science and Technology Project of Education Department of Jiangxi Province","award":["GJJ190311, GJJ180308"],"award-info":[{"award-number":["GJJ190311, GJJ180308"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents a hydrogel-based flexible sensor array to detect plantar pressure distribution and recognize the gait patterns to assist those who suffer from gait disorders to rehabilitate better. The traditional pressure detection array is composed of rigid metal sensors, which have poor biocompatibility and expensive manufacturing costs. To solve the above problems, we have designed and fabricated a novel flexible sensor array based on AAM\/NaCl (Acrylamide\/Sodium chloride) hydrogel and PI (Polyimide) membrane. The proposed array exhibits excellent structural flexibility (209 KPa) and high sensitivity (12.3 mV\u00b7N\u22121), which allows it to be in full contact with the sole of the foot to collect pressure signals accurately. The Wavelet Transform-Random Forest (WT-RF) algorithm is introduced to recognize the gaits based on the plantar pressure signals. Wavelet transform realizes the signal filtering and normalization, and random forest is responsible for the classification of the processed signals. The classification accuracy of the WT-RF algorithm reaches 91.9%, which ensures the precise recognition of gaits.<\/jats:p>","DOI":"10.3390\/s21175964","type":"journal-article","created":{"date-parts":[[2021,9,6]],"date-time":"2021-09-06T21:47:38Z","timestamp":1630964858000},"page":"5964","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Plantar Pressure Detection System Based on Flexible Hydrogel Sensor Array and WT-RF"],"prefix":"10.3390","volume":"21","author":[{"given":"Wei","family":"Liu","sequence":"first","affiliation":[{"name":"School of Electrical and Automation Engineering, East China Jiaotong University, Nanchang 330013, China"}]},{"given":"Yineng","family":"Xiao","sequence":"additional","affiliation":[{"name":"School of Electrical and Automation Engineering, East China Jiaotong University, Nanchang 330013, China"}]},{"given":"Xiaoming","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Electrical and Automation Engineering, East China Jiaotong University, Nanchang 330013, China"}]},{"given":"Fangming","family":"Deng","sequence":"additional","affiliation":[{"name":"School of Electrical and Automation Engineering, East China Jiaotong University, Nanchang 330013, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1970","DOI":"10.1109\/LRA.2020.2970656","article-title":"Two Shank-Mounted IMUs-Based Gait Analysis and Classification for Neurological Disease Patients","volume":"5","author":"Wang","year":"2020","journal-title":"IEEE Robot. 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