Kind Of Networked Control System Research Articles

Stability for a kind of networked control systems with time delays and uncertainties

In this paper, we studied stability for a class of Networked Control Systems (NCSs) with time-delays and uncertainties. At the beginning, the concepts of Linear Matrix Inequality (LMI) and Lyapunov stability are given by definitions. Then the arctle guaranteed the closed-loop function and the controller gain K is obtained by solving matrix inequalities. Finally, numerical examples are employed to verify the efficiency of the proposed methods.

Fault tolerant control for fixed set-point control nonlinear networked control systems

This paper proposes an approach for achieving fault tolerant control algorithm for a kind of networked control system which is fixed set-point control and with nonlinear plant. We firstly describe the nonlinear networked control system and linearize the model of the plant at the operating point, then construct a synthesis model of the whole system, which includes all relevant factors in our research such as network induced time delay, data packet loss, the faults of sensors and actuators etc. Based on this model, the stability condition in meaning square sense of the system is gained by constructing a Lyapunov function. Then the fault tolerant control algorithm is obtained from the stability condition. Lastly, a numerical example is used to prove the validity of the theory.

A non-uniform multi-rate control strategy for a Markov chain-driven Networked Control System

In this work, a non-uniform multi-rate control strategy is applied to a kind of Networked Control System (NCS) where a wireless path tracking control for an Unmanned Ground Vehicle (UGV) is carried out. The main aims of the proposed strategy are to face time-varying network-induced delays and to avoid packet disorder. A Markov chain-driven NCS scenario will be considered, where different network load situations, and consequently, different probability density functions for the network delay are assumed. In order to assure mean-square stability for the considered NCS, a decay-rate based sufficient condition is enunciated in terms of probabilistic Linear Matrix Inequalities (LMIs). Simulation results show better control performance, and more accurate path tracking, for the scheduled (delay-dependent) controller than for the non-scheduled one (i.e. the nominal controller when delays appear). Finally, the control strategy is validated on an experimental test-bed.

H<sub>∞</sub> Robust Control for Networked Control System with Short Time-Delay

For a kind of networked control systems with short time-delay, establish discrete time-invariant system model. Construct the Lyapunov function based on the Lyapunov asymptotic stability principle. Using Linear Matrix Inequalities method given the sufficient condition of H∞ robust controller design method of closed-loop feedback control systems. Matlab simulation indicates the effectiveness and correctness of the controller design.

Analysis of Time Delay and Packet Dropouts Based on State Observer for a Kind of Networked Control System

Against to single packet transmission in networked control system (NCS), it was researched the influence on stability of system caused by long time- delay and packet dropouts in this paper. Firstly, it was built the discrete system model, set up state observer, taken Lyapunov theorem, and gotten the time-lag condition for system’s stability by analyzing its augmented matrix. It also was set up free-weighting matrices, changed the stability condition into Linear Matrix Inequality (LMI) that was easy to get a solution through LMI tools and decrease the conservatism of result

Robust output feedback H∞ control for networked control systems based on the occurrence probabilities of time delays

This article is concerned with the problem of robust H ∞ output feedback control for a kind of networked control systems with time-varying network-induced delays. Instead of using boundaries of time delays to represent all time delays, the occurrence probability of each time delay is considered in H∞ stability analysis and stabilisation. The problem addressed is the design of an output feedback controller such that, for all admissible uncertainties, the resulting closed-loop system is stochastically stable for the zero disturbance input and also simultaneously achieves a prescribed H∞ performance level. It is shown that less conservativeness is obtained. A set of linear matrix inequalities is given to solve the corresponding controller design problem. An example is provided to show the effectiveness and applicability of the proposed method.

Mean square exponential stabilization of networked control systems with Markovian packet dropouts

This paper considers the mean square stabilization for a kind of network control system (NCS) in which there exist network-induced delay and stochastic packet dropout between sensor and controller. This kind of NCS is modelled as a Markovian switched system with two subsystems. Using the average dwell time method, we design a state feedback controller to guarantee that NCS be mean square exponentially stable. An illustrative example is provided to demonstrate the effectiveness of the proposed results.

Observer-based fault-tolerant control for a class of networked control systems with transfer delays

Abstract In this paper, an observer-based fault-tolerant control (FTC) method is proposed for a class of networked control systems (NCSs) with transfer delays. Markov chain is employed to characterize the transfer delays. Then, such kind of networked control systems are modelled as Markovian jump systems. An observer-based FTC scheme using the delayed state information and the estimated fault value is presented to guarantee the stability of the faulty systems. An inverted pendulum example is used to illustrate the efficiency of the proposed method.

A robust fault-tolerant control strategy for networked control systems

Networked control systems (NCS) are one type of distributed control systems where serial communication networks is used to exchange system information and control signals between various physical components of the systems that may be physically distributed. The existence of real-time network in the feedback control loop makes analysis and design of an NCS complex, and conventional control theories such as synchronized control and non-delayed sensing and actuation must be reevaluated prior to application to networked control systems. NCS is a kind of feedback control systems where the control loops are closed through real-time control network. The performance of the closed-loop system is not only determined by the characteristics of the control system, but also determined by the scheduling manner imposed by network. In this paper, adjustable deadbands are explored as a solution to reduce network traffic in networked control systems and we presented a new modeling method for networked control systems with random time delays and communication constraints based on quasi-T–S fuzzy models. The integrity design for the kind of networked control systems is analyzed based on robust fault-tolerant control theory and information scheduling. Parametric expression of controller is given based on feasible solution of linear matrix inequality (LMI). After detailed theoretical analysis, this paper also provides the simulation results, which further validate the proposed scheme.

Modeling and Stability Analysis of Multi-Rate Networked Control Systems with Multiple Control Loops

A kind of multi-input and multi-output network control system with multiple independent control loops is examined in this paper. The controller of each control loop is connected with the sensor and actuator by a network and each control loop has a different sampling period. The whole mathematical model of this kind of networked control system is set up when the maximum network-induced delay is smaller than one sampling period. And the sufficient condition subject to the asymptotic stability of this kind of networked control system is derived based on the theorem for estimation of feature value deduced from perturbation theory. The research results of this paper have significance in the analysis and design of this kind of networked control system or a similar networked control system.

Robust Integrity Design for Nonlinear Networked Control Systems

Implementing a control system over a communication network induces inevitable time delays and packet dropout that degrade performance and can even cause instability. In this paper, adjustable deadbands are explored as a solution to reduce network traffic in networked control system and we presented a new modeling method for nonlinear networked control system with random time delays and communication constraints based on quasi T-S fuzzy models. The stability for the kind of networked control system is analyzed based on robust stability theory and information scheduling. Parametric expression of controller is given based on feasible solution of linear matrix inequality (LMI). A numerical example is given to illustrate the results.

Research on fault-tolerant control of networked control systems based on information scheduling *

A kind of networked control system is studied; the networked control system with noise disturbance is modeled based on information scheduling and control co-design. Augmented state matrix analysis method is introduced, and robust fault-tolerant control problem of networked control systems with noise disturbance under actuator failures is studied. The parametric expression of the controller under actuator failures is given. Furthermore, the result is analyzed by simulation tests, which not only satisfies the networked control systems stability, but also decreases the data information number in network channel and makes full use of the network resources.

Research on robust fault-tolerant control for networked control system with packet dropout

Abstract A kind of networked control system with network-induced delay and packet dropout, modeled on asynchronous dynamical systems was tested, and the integrity design of the networked control system with sensors failures and actuators failures was analyzed using hybrid systems technique based on the robust fault-tolerant control theory. The parametric expression of controller is given based on the feasible solution of linear matrix inequality. The simulation results are provided on the basis of detailed theoretical analysis, which further demonstrate the validity of the proposed schema.