Output Feedback Stabilization Of Time-delay Nonlinear Systems With Multiple Uncertainties

Compared with traditional linear systems,nonlinear systems can more widely utilized in the actual industrial environment such as the biological chemical system and the electrical power system,etc.Because of its nature description of the system is more accurate and and authentic description of nonlinear systems,so the form of expression is more complex and diverse.Control design has also become the hot spot and difficulty in the nonlinear control theory.Ulteriorly,what is clear thing is that the law of things transformations have a variety of unpredictable uncertainties and time delays,which have a great bad impact on the stability of the control system,or even cause the system instability.Therefore,in the past decades,the stability of uncertain nonlinear systems and time-delay uncertain nonlinear systems have become the vital topic of recent research.The main investigation of this paper are as follows:This part investigates the problem of global output feedback stabilization for a class of nonlinear systems with multiple uncertainties.A remarkable feature lies in that the system to be considered is not only involved dynamic and parametric uncertainties but also the measurement output affected by an uncertain continuous function,which leads to the obstacles in the constructions of a state observer and a controller.By revamping the double-domination approach with the skillful implantation of a dynamic gain scheme and nonnegative integral functions,a new design strategy is established by which a global output feedback stabilizer together with a novel state observer can be constructed successfully.The novelty of the presented design is attributed to a perspective in dealing with the output feedback stabilization undergone the unknown continuous(time-varying)output function and dynamic/parametric uncertainties.Finally,the effectiveness of the theoretical results can be illustrated by an illustrative example.This part is concerned with two different types of uncertainties in the time-varying delay nonlinear systems.Compared with some related celebrated works,the considered systems allow the parameter uncertainty in the output function,the dynamic uncertainty of the unmeasurable state,and the existence of continuous external disturbances.A continuous output feedback controller is constructed by utilizing a new restructured integral function and the double-domination method,which guarantees the states convergence of the closed-loop system.Finally,a simulation example is given to demonstrate the effectiveness of the theoretical results.