{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T16:59:39Z","timestamp":1788454779819,"version":"build-2803163510"},"reference-count":24,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,16]],"date-time":"2025-09-16T00:00:00Z","timestamp":1757980800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key R&amp;D Program of China","doi-asserted-by":"publisher","award":["2022YFC3601700"],"award-info":[{"award-number":["2022YFC3601700"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key R&amp;D Program of China","doi-asserted-by":"publisher","award":["2022YFB4703500"],"award-info":[{"award-number":["2022YFB4703500"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key R&amp;D Program of China","doi-asserted-by":"publisher","award":["62273325"],"award-info":[{"award-number":["62273325"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key R&amp;D Program of China","doi-asserted-by":"publisher","award":["62125307"],"award-info":[{"award-number":["62125307"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key R&amp;D Program of China","doi-asserted-by":"publisher","award":["62303444"],"award-info":[{"award-number":["62303444"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Natural Science Foundation of China","award":["2022YFC3601700"],"award-info":[{"award-number":["2022YFC3601700"]}]},{"name":"National Natural Science Foundation of China","award":["2022YFB4703500"],"award-info":[{"award-number":["2022YFB4703500"]}]},{"name":"National Natural Science Foundation of China","award":["62273325"],"award-info":[{"award-number":["62273325"]}]},{"name":"National Natural Science Foundation of China","award":["62125307"],"award-info":[{"award-number":["62125307"]}]},{"name":"National Natural Science Foundation of China","award":["62303444"],"award-info":[{"award-number":["62303444"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomimetics"],"abstract":"<jats:p>The phase detection of abnormal gait and the prediction of lower-limb angles are key challenges in controlling lower-limb exoskeletons. This study simulated three types of abnormal gaits: scissor gait, foot-drop gait, and staggering gait. To enhance the recognition capability for abnormal gait phases, a four-discrete-phase division for a single leg is proposed: pre-swing, swing, swing termination, and stance phases. The four phases of both legs further constitute four stages of walking. Using the Euler angles of the ankle joints as inputs, the capabilities of a Convolutional Neural Network and a Support Vector Machine in recognizing discrete gait phases are verified. Based on these discrete gait phases, a continuous phase estimation is further performed using an adaptive frequency oscillator. For predicting the lower-limb motion angle, this study innovatively proposes an input scheme that integrates three-axis ankle joint angles and continuous gait phases. Comparative experiments confirmed that this information fusion scheme improved the limb angle prediction accuracy, with the Convolutional Neural Network\u2013Long Short-Term Memory network yielding the best prediction results.<\/jats:p>","DOI":"10.3390\/biomimetics10090623","type":"journal-article","created":{"date-parts":[[2025,9,16]],"date-time":"2025-09-16T10:06:25Z","timestamp":1758017185000},"page":"623","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Abnormal Gait Phase Recognition and Limb Angle Prediction in Lower-Limb Exoskeletons"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6458-803X","authenticated-orcid":false,"given":"Sheng","family":"Wang","sequence":"first","affiliation":[{"name":"School of Mechanical and Electrical Engineering, Xi\u2019an University of Architecture and Technology, Xi\u2019an 710055, China"},{"name":"Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4855-9914","authenticated-orcid":false,"given":"Chunjie","family":"Chen","sequence":"additional","affiliation":[{"name":"Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaojun","family":"Wu","sequence":"additional","affiliation":[{"name":"School of Mechanical and Electrical Engineering, Xi\u2019an University of Architecture and Technology, Xi\u2019an 710055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"211","DOI":"10.1109\/TNSRE.2019.2950309","article-title":"Gait trajectory and event prediction from state estimation for exoskeletons during gait","volume":"28","author":"Tanghe","year":"2019","journal-title":"IEEE Trans. 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