Output Feedback Control For Nonlinear Quadratic Systems With Incomplete Measurements

During the past years,the control problem of the nonlinear systems has received much attention in the field of control.The nonlinear quadratic systems as a special form of the nonlinear systems have come to play an important role in practical application,such as physics,ecology,natural sciences,engineering and so on.Hence,nonlinear quadratic systems have aroused much attention and obtained many research results.In recent years,the study of asymptotically stability and finite-time stability of the nonlinear quadratic system has became a key point in the research of many scholars.In this paper,by designing the observer-state feedback controller and dynamic output feedback controller,the problems of stochastic stability and finite-time stochastic stability for a class of nonlinear quadratic systems with incomplete measurements are investigated.The effectiveness of the proposed methodology is shown through the numerical examples.The main work of this paper is given as follows:1.The problem of output feedback control for a class of discrete-time nonlinear quadratic systems with quantization effects and missing measurements is studied.The measured output of system is quantized by a logarithmic quantizer.Moreover,the missing measurements are modeled by introducing a diagonal matrix composed of a series of mutually independent random variables satisfying certain probabilistic distributions on the interval [0,1].In this paper,the output feedback controller design method is provided,which guarantees the zero equilibrium point of the closed-loop system is stochastic stability.By using LMI technique,the sufficient condition is derived for computing the desired controller gain matrix and observer gain matrix of the system.Finally,a numerical example is presented to demonstrate the effectiveness of the proposed method.2.The problem of the finite-time stochastic boundedness and stabilization for a class of discrete-time nonlinear quadratic systems with stochastic parametric uncertainty and missing measurement is investigated.The measurement-missing phenomena are modeled by a Bernoulli distributed stochastic variable taking valueof 0 or 1.The purpose of the problem under consideration is to design a dynamic output feedback controller such that the closed-loop system is finite-time stochastic bounded.Then,by using a similar method,the finite-time stochastic stability for the closed-loop system without exogenous disturbance is also established as a corollary.Finally,a numerical example is presented to demonstrate the effectiveness of the proposed method.