{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T05:08:29Z","timestamp":1778821709508,"version":"3.51.4"},"reference-count":36,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T00:00:00Z","timestamp":1777593600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Algorithms"],"abstract":"<jats:p>Objective: This study investigates the optimization of surface EMG (sEMG) classification for seven transtibial movements using short analysis windows (64 ms) suitable for real-time control of below-knee prostheses. Methods: We systematically evaluated feature engineering strategies, dimensionality reduction techniques, and classification approaches using linear Support Vector Machines on four-channel sEMG data from the transtibial region. We compared amplitude-based versus derivative-based time-domain features, integrated frequency-domain features, and implemented multi-window majority voting with 50% overlap. Results: Evaluated across nine subjects (four male, five female), the optimized system achieves a population-level accuracy of 70.16%\u00b17.09% with multi-window majority voting (per-subject range: 60.71\u201378.57%), with voting consistently improving accuracy over single-window classification by +7.06% on average. We demonstrate that PCA provides zero benefit for linear classifiers when all features are retained. Documented failed approaches include adaptive windowing and spectral entropy features. Conclusion: Careful feature engineering combining time-domain (MAV2, RMS, VAR, MAX, LOG, IEMG) and frequency-domain features (MPF, MF, band powers) with multi-window voting substantially recovers accuracy losses from aggressive window reduction while maintaining sub-100 ms latency suitable for prosthetic control. This work provides a validated methodology across multiple subjects for optimizing EMG classification latency\u2013accuracy trade-offs, demonstrates that PCA is unnecessary for linear classifiers with well-engineered features, and documents negative results to guide future prosthetic control research.<\/jats:p>","DOI":"10.3390\/a19050351","type":"journal-article","created":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T16:54:07Z","timestamp":1777654447000},"page":"351","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Optimizing EMG-Based Transtibial Movement Classification for Real-Time Prosthetic Control: A Feature Engineering and Multi-Window Voting Study"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2453-371X","authenticated-orcid":false,"given":"Carlos Gabriel","family":"Mireles-Preciado","sequence":"first","affiliation":[{"name":"Faculty of Engineering, Universidad Aut\u00f3noma de Quer\u00e9taro (UAQ), Quer\u00e9taro 76010, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2230-6751","authenticated-orcid":false,"given":"Diana Carolina","family":"Toledo-P\u00e9rez","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Universidad Aut\u00f3noma de Quer\u00e9taro (UAQ), Quer\u00e9taro 76010, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7501-5272","authenticated-orcid":false,"given":"Roberto Augusto","family":"G\u00f3mez-Loenzo","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Universidad Aut\u00f3noma de Quer\u00e9taro (UAQ), Quer\u00e9taro 76010, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2838-4854","authenticated-orcid":false,"given":"Marcos","family":"Aviles","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Universidad Aut\u00f3noma de Quer\u00e9taro (UAQ), Quer\u00e9taro 76010, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8598-5600","authenticated-orcid":false,"given":"Juvenal","family":"Rodr\u00edguez-Res\u00e9ndiz","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Universidad Aut\u00f3noma de Quer\u00e9taro (UAQ), Quer\u00e9taro 76010, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1832","DOI":"10.1109\/TNSRE.2017.2687761","article-title":"Study on Interaction between Temporal and Spatial Information in Classification of EMG Signals for Myoelectric Prostheses","volume":"25","author":"Menon","year":"2017","journal-title":"IEEE Trans. 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