{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T09:45:07Z","timestamp":1785836707804,"version":"3.56.0"},"reference-count":45,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T00:00:00Z","timestamp":1785715200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Specialized Intelligent Manufacturing Engineering Laboratory","award":["PT2025KJS002"],"award-info":[{"award-number":["PT2025KJS002"]}]},{"award":["PT2025KJS002"],"award-info":[{"award-number":["PT2025KJS002"]}],"id":[{"id":"https:\/\/ror.org\/03v61g875","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Shandong Province Higher Education Institutions Marine Vessel Special Motor Key Technology Development and Component Manufacturing University-Enterprise Collaborative Innovation Center","award":["PT2025KJS005"],"award-info":[{"award-number":["PT2025KJS005"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomimetics"],"abstract":"<jats:p>In recent years, the potential of exoskeletons to enhance human capabilities has attracted significant research interest. Nevertheless, the control of Rehabilitation Lower-Limb Exoskeletons (RLLEs) is challenging because of their strong nonlinear behaviour. In the paper, a Grey Fuzzy Sliding-Mode (GFSM) controller, which is designed based on the optimization accuracy and estimation capability of the fuzzy logic system, was used for trajectory tracking of a RLLE\u2019s joints. This paper presents the tuning of the controller parameters optimally using Grey Wolf Optimization (GWO) integrated with an Interval Type-2 Fuzzy Logic System (IT2FLS) in real-time. The GFSM was selected as the controller law, in which initially, GWO was used to tune the parameters based on the estimated RLLE\u2019s mathematical model. The optimal tuned parameters were employed to determine the defuzzification range of the fuzzy logic system. IT2FLS was provided to tune the real-time controller parameters. The performance of the GFSM was validated by human-RLLE experiments which showed superior performance compared to other conventional controllers. The experimental results show that the controller achieved reductions in the average error of 81.8%, 82.9%, 84.1%, and 80.6%, respectively, compared with conventional adaptive control methods. These findings indicate that the GFSM can be used to improve motor function recovery in individuals with hemiplegia. By integrating biomechanically inspired motion assistance with IT2FLS, our proposed GFSM controller contributes to the development of biomimetic rehabilitation exoskeletons capable of reproducing natural human gait.<\/jats:p>","DOI":"10.3390\/biomimetics11080546","type":"journal-article","created":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T12:57:56Z","timestamp":1785761876000},"page":"546","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Adaptive Sliding-Mode Controller with Grey Wolf Optimization and Interval Type-2 Fuzzy Logic System for Rehabilitation Lower-Limb Exoskeletons"],"prefix":"10.3390","volume":"11","author":[{"given":"Liancheng","family":"Zheng","sequence":"first","affiliation":[{"name":"School of Mechanical Engineering, Shandong Huayu University of Technology, Dezhou 253034, China"},{"name":"Department of Mechanical and Manufacturing Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, Bangi 43600, Selangor, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6364-6392","authenticated-orcid":false,"given":"Mohammad","family":"Soleimani Amiri","sequence":"additional","affiliation":[{"name":"Faculty of Artificial Intelligence and Cyber Security, Universiti Teknikal Malaysia Melaka, Durian Tunggal 76100, Melaka, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5907-3736","authenticated-orcid":false,"given":"Rizauddin","family":"Ramli","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Manufacturing Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, Bangi 43600, Selangor, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nurul Hamizah","family":"Mohamed","sequence":"additional","affiliation":[{"name":"Faculty of Artificial Intelligence and Cyber Security, Universiti Teknikal Malaysia Melaka, Durian Tunggal 76100, Melaka, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"280","DOI":"10.1186\/s12951-024-02548-8","article-title":"Application and advances of biomimetic membrane materials in central nervous system disorders","volume":"22","author":"Liao","year":"2024","journal-title":"J. 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