Adaptive robust dynamic surface control for uncertain strict‐feedback nonlinear systems using fuzzy logic systems. Issue 2 (6th November 2019)

• Record Type: Journal Article
• Authors: Chen, Sanyan; Wang, Yuchao; Shi, Wenrui; Wu, Hansheng
• Is Part Of: Asian journal of control. Volume 23:Issue 2(2021)
• Page Start: 761
• Page End: 773
• Publication Date: 2019-11-06
• Subjects: adaptive robust control -- backstepping design -- dynamic surface control -- fuzzy logic systems; Automatic control -- Periodicals; Control theory -- Periodicals; 629.805
• DOI: 10.1002/asjc.2253
• Languages: English
• ISSNs: 1561-8625

Abstract

Abstract: In this paper, an adaptive robust stabilization problem is dealt with for a class of uncertain strict‐feedback nonlinear systems in the presence of unknown structure uncertainties, external disturbances, and unknown time‐varying virtual control coefficients. It is not required to know the upper bounds of external disturbances, as well as the upper and lower bounds of unknown time‐varying virtual control coefficients. The controller is designed by adopting backstepping. In addition, to avoid suffering from the problem of 'explosion of terms', a dynamic surface control approach is employed by introducing the first‐order low‐pass filter. Furthermore, at every step of the backstepping design procedure, fuzzy logic systems are used to approximate the unknown structure uncertainties. In particular, the norms of weight matrices and the upper bounds of approximation errors of fuzzy logic systems are supposed to be unknown. It is also shown that the proposed controller can guarantee the uniform boundedness of uncertain strict‐feedback nonlinear systems. Finally, the simulation for a single‐link manipulator actuated by a brush DC motor is carried out to illustrate the validity of the proposed controller.