Adaptive Fuzzy Dynamic Surface Control of Nonlinear Constrained Systems With Unknown Virtual Control Coefficients

• Published in: IEEE transactions on fuzzy systems Vol. 28; no. 8; pp. 1737 - 1747
• Main Authors: Wang, Lijie, Chen, C. L. Philip
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.08.2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Adaptive control; Adaptive dynamic surface control; Adaptive systems; Backstepping; Coefficients; Complexity theory; Constraints; dead zone; Explosions; Feedback control; full state constraints; Fuzzy control; Fuzzy logic; Liapunov functions; Lyapunov methods; Nonlinear control; Nonlinear systems; Sliding mode control; unknown virtual control coefficients
• ISSN: 1063-6706; 1941-0034
• DOI: 10.1109/TFUZZ.2019.2921277

This paper studies the problem of adaptive fuzzy dynamic surface control (DSC) of nonstrict-feedback nonlinear systems subject to unknown virtual control coefficients, dead zone, and full state constraints. The Nussbaum gain technique is used to overcome the difficulty caused by the unknown virtual control coefficients. By utilizing the information of tan-type barrier Lyapunov function, the requirement of full state constraints is successfully achieved. In addition, to handle the problem of "explosion of complexity" resulted from backstepping itself, a DSC approach using the sliding mode differentiator is introduced. Then, based on backstepping control, we develop a new adaptive fuzzy DSC strategy, which ensures that all state constrains are not violated via designing parameters appropriately. Meanwhile, other signals existing in the closed-loop system are bounded. Finally, comparative results are provided to illustrate the effectiveness of the proposed approach.