Control Strateg Ydesgin For Nonlinear Sysetm Based On Backstepping Control

It is very important to study on the nonlinear systems, since nonlinear characteristicsis the common phenomenon in engineering area. This paper researches the control designproblem of a class of nonlinear system based on combining sliding mode control theory,and backstepping control technique to achieve the stable tracking performance. Throughtheoretical analysis and numerical simulations, the validity and effectiveness ofdescription method is demonstrated. The main work of this paper includes the followingaspects.Firstly, the research backgrounds and meaning of the paper is introduced, and thesome nonlinear control strategies are introduced.Secondly, the theory of the backstepping control and sliding mode control arepresented. The stable tracking control problem of a class of strict feedback nonlinearsystem is considered. The backstepping controller is developed to obtain the stabletracking. In the framework of Lyapunov stability theory, the stability of the closed-loopsystem is proved, and the effectiveness of the designed control scheme is evaluated bysimulation.Thirdly, the stable tracking control problem of a class of strict feedback nonlinearsystem is taken into consideration with uncertainty. The sliding mode control is used tohandle the uncertainty with the known upper bound. Then based on the design procedureof backstepping control, the robust backstepping control scheme is designed. And basedon Lyapunov stability theory, the stability of the closed-loop system is proved under theinfluence of uncertainty. Simulation is done to verify the performance of robustbackstepping control strategy.At last, the stable tracking control problem of a class of strict feedback nonlinearsystem is regarded in the presence of uncertainty the upper bound is unknown. Unknownnonlinear function is approximated online by RBFNN, and the uncertainty is handled.Then based on backstepping control technique, the RBFNN-based adaptive dynamicsurface controller is developed. Moreover, on the basis of Lyapunov stability theory, thestability of the closed-loop system is proved under the influence of uncertainty. Thetracking performance of the designed control strategy is testified through simulation.