Research On Control Of Sensor Networked Systems Under Communication Constraints And Uncertainties

Networked control systems(NCSs),also known as integrated communication systems,refer to feedback control systems that form a closed loop through the network.In NCSs,wireless sensor networked systems(SNSs)are a kind of more general control system.SNSs are composed of a series of sensor nodes.Each sensor node can not only receive information from itself,but also receive information from its neighbor nodes according to a given sensor topology.In addition,it is always impossible to obtain a correct measurement of the state of the system in the actual system.In recent years,the design of controllers that only require some state variables has attracted a lot of attention.Therefore,the observer-based controller research has been extended to sensor networked systems.On the other hand,due to the network delays and bandwidth constraints,poor hardware and other reasons,the problem of communication limitation cannot be ignored in research.Therefore,the research of observer-based controllers in sensor networked systems under communication constraints is of great significance.Based on the sensor networked system,this paper studies the problem of observerbased controllers under communication constraints.The main research contents include the following three aspects:(1)The observer-based control feedback problem in sensor networked systems with distributed hybrid-triggered mechanism and input quantization is studied.Firstly,in order to estimate the state variables that are difficult to measure,a new type of observer model is proposed based on multi-channel coupled transmission signals.Secondly,in order to achieve a balance between improving system performance and saving network resources,a distributed hybrid-trigger scheme with delay was adopted.In addition,using Lyapunov functional theory and stochastic stability analysis theory,sufficient conditions to ensure the asymptotic stability of the system are given.Finally,a numerical simulation example verifies the effectiveness of the method.(2)Considering the distributed adaptive event-triggered mechanism and multiple network attacks,the output feedback controller problem of Markov jump linear system in the framework of random saturated sensor networks is studied.First of all,for the random switching of the controlled model and the sensor network connection topology in the network system,the Markov jump system is introduced for modeling.Secondly,after introducing distributed adaptive event-triggered mechanism and randomly occurring cyber attacks,the observer-based controller model is established.Next,using Lyapunov functional theory,sufficient conditions are given to make the closed loop system stochastic asymptotic stability.Furthermore,the observer and controller gains are obtained by solving the LMIs with the aid of the singular value decomposition of the matrix.Finally,a simulation example is proposed to verify the feasibility.(3)The non-fragile control problem of a class of T-S fuzzy sensor networked system with distributed event-triggered mechanism is studied.Firstly,considering the influence of distributed event-triggered mechanism and uncertainty of control parameters,a closed-loop system based on non-fragile observer is constructed.Then the Lyapunov functional theory is used to obtain sufficient conditions to ensure the asymptotic stability of the system.On this basis,the LMIs are solved to obtain the observer and controller gains.Finally,a numerical simulation example verifies the validity of the model.