Tracking Control Design For Two Types Of Uncertain High-order Nonlinear Systems

It is well known that there are always randomness and uncertainties in practical industrial systems,so the model of nonlinear systems is more accurate to characterize the actual industrial systems than that of linear systems.Therefore,the control design problem of nonlinear systems has always been a hot topic in the field of control theory,and the output tracking control problem of nonlinear systems has always been regarded as one of the focus of the nonlinear control theory and is widely used in aerospace,military manufacturing and other fields.Further more,compared with the output tracking control,the finite-time output tracking control of the nonlinear system has stronger robustness,self-adaptability and anti-interference,Therefore,the tracking control and practical finite time tracking control of high-order nonlinear systems have theoretical meanings and practical applications.The main contents of this paper are given as follows:?.Output tracking control of high-order nonlinear systems with dynamic uncertaintiesThis part mainly studies the output tracking control problem for a class of nonlinear systems with zero dynamic.On the basis of adding a power integrator method and approximation technique,an appropriate controller is proposed to guarantee that the tracking error turns to a preassigned neighborhood of the origin.The systems under investigation allow unmeasurable dynamic uncertainties,unknown nonlinear functions and unknown high-order terms.As an application,a numerical example and a practical example are provided to illustrate the superiority of the control strategy.?.Practical finite-time output tracking control for a class of high-order nonlinear systemsThis part investigates the practical finite-time almost disturbance decoupling problem for a class of high-order nonlinear systems with multiple disturbances.On the basis of prescribed performance control,almost disturbance decoupling and backstepping technique,a practical finite-time tracking controller is designed to ensure that the output tracking error converge to a predefined small domain within a finite time.As an application,an example is provided to illustrate the effectiveness of the proposed strategy.