Research On Feedback Control Problems Of High-order Nonlinear Systems With Zero Dynamics And Asymmetric Constraint

With the application and development of computer control theory in intelligent robot,mechanical automation,social public facilities and aerospace fields,a variety of new largescale nonlinear control systems appear in people’s vision.In traditional data sample detection methods,it is often difficult to clearly understand the complex mechanism structure inside the system,which leads to a variety of uncertainties in the establishment of the model.These uncertainties will not only reduce the stability of the system,but even destroy the performance of the system,resulting in the system unable to find the optimal solution.On the other hand,due to the differences of the output constraints and the complexity of external disturbance,developing more appropriate and effective control strategies becomes particularly important.Combining theory with practical application,the control problems of two kinds of uncertain nonlinear systems are studied in this paper,which is divided into two parts:I.Control design of high-order nonlinear systems with zero dynamic and asymmetric output constraintsThe control design of a class of high-order nonlinear systems with zero dynamics and asymmetric constraints is studied.For high-order nonlinear systems with zero dynamic and asymmetric constraints,a new continuous state feedback controller is designed by using Lyapunov barrier function and a series of non-negative integral functions with sign functions.The designed controller can drive the states of the system converge to the origin.The proposed control scheme is different from the existing control methods since it can simultaneously deal with the stabilization problem of high-order nonlinear systems with asymmetric constraints and dynamic uncertainty of parameters.Finally,a simulation example is given to verify the effectiveness of the proposed control method.II.Control design of high-order uncertain nonlinear systems with zero dynamics and external interferenceThe control design of a class of high-order nonlinear systems with zero dynamic and asymmetric constraints and complex external perturbations is studied.For uncertain high-order nonlinear systems with complex external interference and zero dynamics,an adaptive controller is designed to make the states of the closed-loop system converge to a compact set.Different from the traditional method,a relatively simple logic is proposed.Based on the state feedback stabilization,it can effectively deal with the interference brought by the complex disturbance and make the system states converge quickly and effectively.