{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T16:11:10Z","timestamp":1774627870868,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2021,12,15]],"date-time":"2021-12-15T00:00:00Z","timestamp":1639526400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004421","name":"Warsaw University of Technology","doi-asserted-by":"publisher","award":["504\/04577\/1142\/44.000000"],"award-info":[{"award-number":["504\/04577\/1142\/44.000000"]}],"id":[{"id":"10.13039\/501100004421","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Mechanomyography (MMG) is a technique of recording muscles activity that may be considered a suitable choice for human\u2013machine interfaces (HMI). The design of sensors used for MMG and their spatial distribution are among the deciding factors behind their successful implementation to HMI. We present a new design of a MMG sensor, which consists of two coupled piezoelectric discs in a single housing. The sensor\u2019s functionality was verified in two experimental setups related to typical MMG applications: an estimation of the force\/MMG relationship under static conditions and a neural network-based gesture classification. The results showed exponential relationships between acquired MMG and exerted force (for up to 60% of the maximal voluntary contraction) alongside good classification accuracy (94.3%) of eight hand motions based on MMG from a single-site acquisition at the forearm. The simplification of the MMG-based HMI interface in terms of spatial arrangement is rendered possible with the designed sensor.<\/jats:p>","DOI":"10.3390\/s21248380","type":"journal-article","created":{"date-parts":[[2021,12,15]],"date-time":"2021-12-15T21:47:36Z","timestamp":1639604856000},"page":"8380","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["A Coupled Piezoelectric Sensor for MMG-Based Human-Machine Interfaces"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0464-3949","authenticated-orcid":false,"given":"Mateusz","family":"Szumilas","sequence":"first","affiliation":[{"name":"Warsaw University of Technology, Faculty of Mechatronics, Institute of Metrology and Biomedical Engineering, A. Boboli 8 St., 02-525 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6986-251X","authenticated-orcid":false,"given":"Micha\u0142","family":"W\u0142adzi\u0144ski","sequence":"additional","affiliation":[{"name":"Warsaw University of Technology, Faculty of Mechatronics, Institute of Metrology and Biomedical Engineering, A. Boboli 8 St., 02-525 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0531-8563","authenticated-orcid":false,"given":"Krzysztof","family":"Wildner","sequence":"additional","affiliation":[{"name":"Warsaw University of Technology, Faculty of Mechatronics, Institute of Metrology and Biomedical Engineering, A. Boboli 8 St., 02-525 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2499","DOI":"10.1109\/JSEN.2013.2255982","article-title":"Mechanomyography Sensor Development, Related Signal Processing, and Applications: A Systematic Review","volume":"13","author":"Islam","year":"2013","journal-title":"IEEE Sens. J."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1186\/1475-925X-4-67","article-title":"Mechnomyographic amplitude and frequency responses during dynamic muscle actions: A comprehensive review","volume":"4","author":"Beck","year":"2005","journal-title":"Biomed. Eng. Online"},{"key":"ref_3","first-page":"201","article-title":"Muscle sound: Bases for the introduction of a mechanomyographic signal in muscle studies","volume":"21","author":"Orizio","year":"1993","journal-title":"Crit. Rev. Biomed. 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