{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T23:16:21Z","timestamp":1763766981991,"version":"3.40.5"},"reference-count":44,"publisher":"Cambridge University Press (CUP)","issue":"2","license":[{"start":{"date-parts":[[2020,8,13]],"date-time":"2020-08-13T00:00:00Z","timestamp":1597276800000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Robotica"],"published-print":{"date-parts":[[2021,2]]},"abstract":"<jats:title>SUMMARY<\/jats:title><jats:p>Accurate torque control is a critical issue in the compliant human\u2013robot interaction scenario, which is, however, challenging due to the ever-changing human intentions, input delay, and various disturbances. Even worse, the performances of existing control strategies are limited on account of the compromise between precision and stability. To this end, this paper presents a novel high-performance torque control scheme without compromise. In this scheme, a new nonlinear disturbance observer incorporated with equivalent control concept is proposed, where the faster convergence and stronger anti-noise capability can be obtained simultaneously. Meanwhile, a continuous fractional power control law is designed with an iteration method to address the matched\/unmatched disturbance rejection and global finite-time convergence. Moreover, the finite-time stability proof and prescribed control performance are guaranteed using constructed Lyapunov function with adding power integrator technique. Both the simulation and experiments demonstrate enhanced control accuracy, faster convergence rate, perfect disturbance rejection capability, and stronger robustness of the proposed control scheme. Furthermore, the evaluated assistance effects present improved gait patterns and reduced muscle efforts during walking and upstair activity.<\/jats:p>","DOI":"10.1017\/s0263574720000375","type":"journal-article","created":{"date-parts":[[2020,8,13]],"date-time":"2020-08-13T07:59:59Z","timestamp":1597305599000},"page":"291-316","source":"Crossref","is-referenced-by-count":7,"title":["Continuous Finite-Time Torque Control for Flexible Assistance Exoskeleton with Delay Variation Input"],"prefix":"10.1017","volume":"39","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7499-6160","authenticated-orcid":false,"given":"Tao","family":"Xue","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"ZiWei","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tao","family":"Zhang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ou","family":"Bai","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Meng","family":"Zhang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bin","family":"Han","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"56","published-online":{"date-parts":[[2020,8,13]]},"reference":[{"key":"S0263574720000375_ref6","unstructured":"[6] Wang, Z. , Xue, T. , Liang, B. , and Chen, Z. , \u201cBackstepping Based Robust Control for Space Tele-Robot Systems with Finite-Time Convergence,\u201d Proceedings of 2018 IEEE International Conference on Robotics and Biomimetics (ROBIO) (2018) pp. 1419\u20131424."},{"key":"S0263574720000375_ref24","volume-title":"Inequalities","volume":"30","author":"Beckenbach","year":"2012"},{"key":"S0263574720000375_ref11","unstructured":"[11] Meng, W. , Lei, S. , Yin, W. , Shuai, D. and Jingtai, L. , \u201cContinuous Finite-Time Control Approach for Series Elastic Actuator,\u201d Proceedings of IEEE Conference on Decision and Control (2016) pp. 843\u2013848."},{"key":"S0263574720000375_ref8","doi-asserted-by":"publisher","DOI":"10.1007\/978-0-8176-4893-0"},{"key":"S0263574720000375_ref4","unstructured":"[4] Xue, T. , Wang, Z. , Zhang, T. , Zhang, M. and Li, Z. , \u201cThe Control System for Flexible Hip Assistive Exoskeleton,\u201d Proceedings of 2018 IEEE International Conference on Robotics and Biomimetics (ROBIO) (2018) pp. 697\u2013702."},{"key":"S0263574720000375_ref9","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1109\/TAC.2014.2324212","article-title":"Continuous finite-time output regulation for disturbed systems under mismatching condition","volume":"60","author":"Shihua","year":"2015","journal-title":"IEEE Trans. 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