In this paper,the singularity-free predefined-time fuzzy adaptive tracking control problem is studied for non-strict feedback(NSF)nonlinear systems considering mismatched external disturbances.An innovative practical ...In this paper,the singularity-free predefined-time fuzzy adaptive tracking control problem is studied for non-strict feedback(NSF)nonlinear systems considering mismatched external disturbances.An innovative practical predefined-time stability(PPTS)criterion is proposed to provide the theoretical basis for subsequent control design.Compared to the existing predefined-time stability(PTS)criterion,this criterion has a broader application range and can solve the control design issues of nonlinear systems with system uncertainties.Fuzzy logic systems(FLSs)are employed to identify unknown nonlinear functions.Based on the backstepping control technology,a singularity-free predefined-time control(PTC)design method is proposed,in which the hyperbolic tangent function is utilized to avoid the singular problem,and the nature of fuzzy basis function is adopted to resolve the algebraic loop problem.The PPTS of the closed-loop NSF nonlinear system is proven with the Lyapunov theory and the proposed PPTS criterion.Ultimately,the efficiency of the presented PTC design method is verified by several sets of simulations on a single link manipulator system.展开更多
基金supported in part by the National Natural Science Foundation of China under Grant Nos.92267203,62373302,62333009,62176111,and 62333004in part by the Key-Area Research and Development Program of Guangdong Province under Grant No.2023B0303030001+2 种基金in part by the Program for Guangdong Introducing Innovative and Entrepreneurial Teams under Grant No.2019ZT08X214in part by the Natural Science Foundation of Shaanxi Province under Grant No.2024JC-YBQN-0663in part by Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University under Grant No.CX2023084。
文摘In this paper,the singularity-free predefined-time fuzzy adaptive tracking control problem is studied for non-strict feedback(NSF)nonlinear systems considering mismatched external disturbances.An innovative practical predefined-time stability(PPTS)criterion is proposed to provide the theoretical basis for subsequent control design.Compared to the existing predefined-time stability(PTS)criterion,this criterion has a broader application range and can solve the control design issues of nonlinear systems with system uncertainties.Fuzzy logic systems(FLSs)are employed to identify unknown nonlinear functions.Based on the backstepping control technology,a singularity-free predefined-time control(PTC)design method is proposed,in which the hyperbolic tangent function is utilized to avoid the singular problem,and the nature of fuzzy basis function is adopted to resolve the algebraic loop problem.The PPTS of the closed-loop NSF nonlinear system is proven with the Lyapunov theory and the proposed PPTS criterion.Ultimately,the efficiency of the presented PTC design method is verified by several sets of simulations on a single link manipulator system.
