{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T19:27:28Z","timestamp":1791487648473,"version":"4.3.4"},"reference-count":45,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2024,7,25]],"date-time":"2024-07-25T00:00:00Z","timestamp":1721865600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Royal Society","award":["IES\\R1\\201342"],"award-info":[{"award-number":["IES\\R1\\201342"]}]},{"name":"Royal Society","award":["202008440267"],"award-info":[{"award-number":["202008440267"]}]},{"DOI":"10.13039\/501100004543","name":"China Scholarship Council","doi-asserted-by":"publisher","award":["IES\\R1\\201342"],"award-info":[{"award-number":["IES\\R1\\201342"]}],"id":[{"id":"10.13039\/501100004543","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004543","name":"China Scholarship Council","doi-asserted-by":"publisher","award":["202008440267"],"award-info":[{"award-number":["202008440267"]}],"id":[{"id":"10.13039\/501100004543","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Pattern recognition (PR)-based myoelectric control systems can naturally provide multifunctional and intuitive control of upper limb prostheses and restore lost limb function, but understanding their robustness remains an open scientific question. This study investigates how limb positions and electrode shifts\u2014two factors that have been suggested to cause classification deterioration\u2014affect classifiers\u2019 performance by quantifying changes in the class distribution using each factor as a class and computing the repeatability and modified separability indices. Ten intact-limb participants took part in the study. Linear discriminant analysis (LDA) was used as the classifier. The results confirmed previous studies that limb positions and electrode shifts deteriorate classification performance (14\u201321% decrease) with no difference between factors (p &gt; 0.05). When considering limb positions and electrode shifts as classes, we could classify them with an accuracy of 96.13 \u00b1 1.44% and 65.40 \u00b1 8.23% for single and all motions, respectively. Testing on five amputees corroborated the above findings. We have demonstrated that each factor introduces changes in the feature space that are statistically new class instances. Thus, the feature space contains two statistically classifiable clusters when the same motion is collected in two different limb positions or electrode shifts. Our results are a step forward in understanding PR schemes\u2019 challenges for myoelectric control of prostheses and further validation needs be conducted on more amputee-related datasets.<\/jats:p>","DOI":"10.3390\/s24154840","type":"journal-article","created":{"date-parts":[[2024,7,25]],"date-time":"2024-07-25T14:31:07Z","timestamp":1721917867000},"page":"4840","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Unravelling Influence Factors in Pattern Recognition Myoelectric Control Systems: The Impact of Limb Positions and Electrode Shifts"],"prefix":"10.3390","volume":"24","author":[{"given":"Bingbin","family":"Wang","sequence":"first","affiliation":[{"name":"Department of Engineering, King\u2032s College London, London WC2R 2LS, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinglin","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Engineering, King\u2032s College London, London WC2R 2LS, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Levi","family":"Hargrove","sequence":"additional","affiliation":[{"name":"Center for Bionic Medicine, Shirley Ryan Ability, Chicago, IL 60611, USA"},{"name":"Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6846-2090","authenticated-orcid":false,"given":"Ernest Nlandu","family":"Kamavuako","sequence":"additional","affiliation":[{"name":"Department of Engineering, King\u2032s College London, London WC2R 2LS, UK"},{"name":"Facult\u00e9 de M\u00e9decine, Universit\u00e9 de Kindu, Site de Lwama II, Kindu, Maniema, Congo"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"473","DOI":"10.1038\/s41551-021-00732-x","article-title":"Toward higher-performance bionic limbs for wider clinical use","volume":"7","author":"Farina","year":"2021","journal-title":"Nat. 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