Finite-horizon H_? Control For Networked Systems With Communication Constraints

Networked control systems are closed-loop control systems in which sensors,controllers,actuators and other system components are connected as network nodes via a shared communication network.The communication resources are usually limited in the process of signal transmissions,which inevitably introduces communication constraints such as data collisions,network congestion and channel competition.Therefore,the communication network needs to join the communication protocol to allocate the rights of each node to use the network.At present,the control analysis and comprehensive research of networked systems are mainly for linear time-invariant systems and deterministic systems.However,the introduction of communication protocols is likely to make many traditional control methods unsuitable for networked systems with communication constraints,and different communication protocols have different effects on the NCSs.Under this background,this thesis is concerned with the H? control problems for several kinds of time-varying networked systems with communication constrains over a finite horizon.The main research contents are as follows:A new observer-based H? controller design method is developed for a class of time-varying networked control systems subject to high-rate communication network and Round-Robin protocol over a finite-horizon.The system under investigation involves multiplicative noise,stochastic time-delays and quantization effects.By applying Lyapunov stability theory and linear matrix inequality technique,a sufficient condition for the existence of the finite-horizon H? controller is derived.The corresponding parameters of the observer and controller are obtained via resorting to a set of recursive matrix inequalities based on cone complementarity linearization method.The proposed controller can ensure both the stability and the prescribed H? performance index of the closed-loop system over a given finite horizon.The H? control problem is investigated for a class of time-varying state-saturated systems with both stochastic parameters and nonlinearities under the stochastic communication protocol.The sensor-to-controller network is considered where only one sensor obtains access to the communication network at each transmission instant.The SCP is adopted to mitigate the undesirable data collision phenomenon.The model transformation technique is employed to simplify the addressed problem,and then the completing squares method is carried out to obtain a sufficient condition for the existence of the finite-horizon H? controller.The controller parameters are characterized by solving two coupled backward recursive Riccati-like difference equations.A simulation example is finally utilized to illustrate the effectiveness and superiority of the proposed controller design scheme.The finite-horizon H? control problem is investigated for a class of discrete nonlinear time-varying systems subject to Weighted Try-Once-Discard communication protocol effects.the equation of state and output under investigation involve both deterministic and stochastic nonlinearities.By resorting to the Taylor series expansion formula,Lyapunov stability theory and cross-amplification lemma,sufficient conditions are established for the existence of the desired observer-based H? controller.The gain matrixes of the controller and observer are obtained by solving a set of recursive linear matrix inequalities.