Turkish Journal of Electrical Engineering and Computer Sciences
Abstract
This paper presents an adaptive backstepping nonsingular fast terminal sliding mode controller integrated with a nonlinear disturbance observer to achieve precise trajectory tracking of robotic manipulators subject to model uncertainties and unknown time-varying disturbances. A dead-zone–based adaptive gain mechanism is introduced to dynamically adjust the control gain according to the deviation of the sliding surface, thereby enhancing robustness and reducing chattering. The proposed reaching law ensures fast, nonsingular, and adaptive convergence, suppressing high-frequency oscillations without compromising stability and the nonlinear disturbance observer enables real-time estimation and compensation of modeling errors, friction, and external disturbances for superior rejection. The semiglobal uniform ultimate boundedness of the closed-loop system is rigorously proven using Lyapunov theory. Simulation results confirm that the proposed method achieves higher tracking accuracy, faster convergence, and better robustness compared with conventional controllers.
DOI
10.55730/1300-0632.4185
Keywords
Nonsingular fast terminal sliding mode, backstepping control, nonlinear disturbance observer, adaptive control, robotic manipulator
First Page
453
Last Page
471
Publisher
The Scientific and Technological Research Council of Türkiye (TÜBİTAK)
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
ZHANG, X, & WANG, X (2026). Adaptive backstepping nonsingular fast terminal sliding mode control for robotic manipulators based on disturbance observer. Turkish Journal of Electrical Engineering and Computer Sciences 34 (3): 453-471. https://doi.org/10.55730/1300-0632.4185
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