{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,17]],"date-time":"2025-11-17T14:25:52Z","timestamp":1763389552220,"version":"3.45.0"},"reference-count":32,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,11,15]],"date-time":"2025-11-15T00:00:00Z","timestamp":1763164800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Dezhou Industrial Robot System Integration Engineering Research Center"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>In this study, we introduce a novel adaptive fault-tolerant sliding mode control strategy for the finite-time control of symmetric robotic manipulators subjected to uncertainties, disturbances and actuator failures. Firstly, we design a novel type of sliding mode manifold termed Practical Fast Terminal Sliding Mode (P-FTSM). P-FTSM exhibits the capability to accelerate convergence speed while ensuring the finite-time convergence of the system. Subsequently, the P-FTSM is integrated with the super-twisting algorithm (STA) to mitigate the chattering of control input. Additionally, a novel K\u221e function is introduced to serve as the gain of the STA. This strategy, which does not require knowledge of the upper bound of the disturbance and fault information, ensures that the gain is tuned according to the disturbance and fault variations, mitigating the adverse effects of high gain and further weakening of the chattering. Simulation results on a two-link symmetric manipulator verify that the proposed method achieves outstanding quantitative performance. The proposed method achieves convergence times of 0.22 and 0.12 s for the joint errors, with root mean square errors (RMSE) of 0.036 and 0.095. The integral absolute errors (IAE) are 0.049 and 0.086, and the total control energy is 943.46. The total variations (TV) of the control signals are 2.86\u00d7103 and 1.64\u00d7103, indicating effectively suppressed chattering. Overall, the proposed strategy ensures high precision, rapid convergence, and strong fault-tolerant capability.<\/jats:p>","DOI":"10.3390\/sym17111978","type":"journal-article","created":{"date-parts":[[2025,11,17]],"date-time":"2025-11-17T14:04:07Z","timestamp":1763388247000},"page":"1978","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Adaptive Fault-Tolerant Super Twisting Control Design Based on K\u221e Function for Symmetric Manipulators"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-3850-3347","authenticated-orcid":false,"given":"Haicheng","family":"Wan","sequence":"first","affiliation":[{"name":"School of Electrical Engineering, Shandong Huayu University of Technology, Dezhou 253000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-6307-1004","authenticated-orcid":false,"given":"Yutao","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Shandong Huayu University of Technology, Dezhou 253000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1848-1565","authenticated-orcid":false,"given":"Ping","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Shandong Huayu University of Technology, Dezhou 253000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-7178-800X","authenticated-orcid":false,"given":"Wendong","family":"Li","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Shandong Huayu University of Technology, Dezhou 253000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,15]]},"reference":[{"key":"ref_1","first-page":"1","article-title":"Gesture Recognition-Based Robust Predefined-Time Admittance Control of Bimanual Teleoperation Without Force\/Torque Measurement","volume":"73","author":"Yang","year":"2024","journal-title":"IEEE Trans. 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