Abstract
This paper addresses the asymptotic control problem of uncertain multi-input and multi-output (MIMO) nonlinear systems. The considered MIMO systems contain unknown virtual control coefficients (UVCCs) and state constraints. A creative Lyapunov function by associating with the lower bounds of UVCCs is presented to counteract the adverse effect deriving from UVCCs. The state constraints are ensured by utilising the barrier Lyapunov function. Moreover, the asymptotic tracking controller is recursively constructed by combining the backstepping technique with fuzzy logic systems. The remarkable character of the designed controller is that the asymptotic tracking performance can be achieved by introducing some smooth functions into adaptive backstepping procedure. In contrast to the existing results, the conditions on the UVCCs are relaxed. Finally, the new control design is illustrated by a practical example.
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No potential conflict of interest was reported by the authors.
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Notes on contributors
Yongchao Liu
Yongchao Liu received the Ph.D. degree in control science and engineering from Harbin Engineering University, Harbin, China, in 2021. He is currently an Associate Professor with the Qingdao University. His research interests include nonlinear adaptive control, fuzzy control and neural network control for nonlinear systems.
Bowen Zeng
Bowen Zeng received the Ph.D. degree in control science and engineering from Harbin Engineering University, Harbin, China, in 2012. He is currently a Lecturer with the Harbin Engineering University. His research interests include ship motion control and embedded system design and application.
Qidan Zhu
Qidan Zhu received the Ph.D. degrees in control theory and control engineering from Harbin Engineering University, Harbin, China, in 2001. He is a Professor with the Harbin Engineering University, Harbin, China. His research interests include robot intelligent control, computer vision and intelligent control theory.
Lipeng Wang
Lipeng Wang received the Ph.D. degree in control science and engineering from Harbin Engineering University, in 2017. His research interests include nonlinear control and model predictive control.