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A novel simultaneous design scheme of H-infinity quantized feedback controller and periodic scheduling protocol for a class of networked control systems (NCSs) with bit rate constraints and time delay is proposed in this paper. A mid-tread uniform quantizers is used and the quantization error is treated as a model uncertainty by utilizing sector-bounded method. Next NCSs is modeled as a discrete-time switched system with parameter uncertainties. The procedures for H-infinity controller design under the static periodic scheduling protocol are given to maintain the asymptotic stability and robust performance of the closed-loop NCSs. Finally a simulation example is given to illustrate effectiveness of the proposed method.

The networked control system was modeled in this paper. According to the actual network conditions, the networked-induced time delay is always varying in a certain range. So, the networked-induced time delay can be divided into the fixed time delay and the random time delay. The long time delay can be taken as packet dropout. What’s more, the drive mode, packets disorder, sampling period, and some assumed conditions were considered carefully in this paper. In order to make the research close to the reality, the round-trip delay of the network between Tsinghua University and Yahoo is measured by sending and receiving data packet every 5 s from Tsinghua side. Simulation showed that the modeling method improved the effectiveness of the system.

This chapter proposes a mixed self and event-triggered sampling scheme (MSE) for the execution of sampling in wireless networked control systems (WiNCSs) by striking a balance between self-triggered sampling (SET) and periodic event-triggered sampling (PET) to achieve a high energy efficiency.

IP-based network delays in networked control systems (NCSs) are inherently nonuniformly distributed and behave with multifractal nature. This chapter proposes a delay distribution-based stability analysis and synthesis approach for a linear system controlled over an IP-based communication network.

A novel integrated design scheme of dynamic dwell time scheduling strategy, dynamic bandwidth allocation policy, and quantized control for networked control systems (NCS) with time delay and communication constraints is proposed in this paper. A scheduling policy is raised to accommodate a limited number of node-controller connections which depend on the periodic communication sequences and dynamic dwell time. Then, the neural network technique is employed to dynamically allocate bit rate for the scheduling nodes. The networked control systems are modeled as discrete-time switched systems with bounded disturbances. Finally, a design procedure for the state feedback controller is presented to guarantee asymptotic stability of the NCS. A simulation example is given to illustrate effectiveness of the proposed method.

For the networked control systems (NCSs) with time-delay and the characteristic of Markovian data dropout, the model is established as Markovian jump linear systems with two running modes without changing the structure of the initial control systems. Furthermore, the condition for the existence of the mode-depended state feedback control law is derived. The design method for state feedback controller is also given. Finally, a numerical example is employed to demonstrate the validity of the method.

This paper presents a novel adaptive event-triggered communication scheme for networked control systems (NCSs) with nonlinearities. Firstly, a novel adaptive event-triggered communication scheme for NCSs with nonlinearities is proposed, which can adaptively adjust the event-triggered communication threshold with respect to dynamic error to save the limited communication resource while ensuring the desired control performance. Secondly, a model of the considered system is built under consideration of the network-induced delay, adaptive event-triggered communication scheme and nonlinearities in a unified framework. Then, sufficient stability and stabilization criteria are obtained to judge the mean-square sense asymptotically stable for the studied system. Finally, two examples illustrate the effectiveness of the developed method.

This paper is concerned with fault detection filter design of certain discrete-time networked systems with delays. Based on the traditional fault detection filter, a novelty fault detection observer was designed to compensate the delay by iteration. The fault reference model was introduced, and an augumented residual system was derived. With the H∞ theory, a fault detection schem was proposed based on the H∞filter. With the LMI, the observer gain and the post filter matrix could be got. Simulation results gave an illustration of the proposed design.

In this paper, a networked ship course control system is considered, and the network-induced delay is the main problem in the networked control system (NCS). A network-based fuzzy adaptive nonlinear sliding model controller is proposed. The sliding surface is constructed with the time delay compensation. The unknown parts in the model, consisting of the external disturbances and the unmodeled dynamics, are approximately estimated by the fuzzy logic system. The sliding mode controller is designed to deal with the bad influence brought by both the time delay and the unknown terms. According to the Lyapunov theorem, the parameter vector of the fuzzy system is updated and the stability of the closed-loop system is proved. Finally, with the network environment simulated using the Truetime toolbox, simulation tests on a Mariner class vessel in waves are performed to validate the effectiveness of the proposed control scheme.

Sensor, network and actuator and etc consist of Networked Control Systems(NCS) that make system flexible but also bring networked delay to system. In real application, networked delay usually is longer than a sampling time of system and affects the whole system’s stability. In this paper, it changes the random long delay into certain long delay, provides a method based on Predictive Functional Control(PFC) with incremented weight concerning about the effect of inputs and designs a reasonable controller that make system stable. Finally, it compares with a traditional PID control through simulation and the result proves that takes the method mentioned in this paper can better make system’s output stable.

For the complexity of network, networked control systems (NCS) have higher level of demands for safety and reliability than general systems. Therefore, the research on fault detection of networked control system has great theoretical and applied value. The networked control systems can be modeled using the Matlab/Simulink. There a state observer is designed, and then a simulation is conducted in allusion to the network’s time-delay problem. Its influence upon the system’s performance shows good.

Focusing on networked control systems with long time-delays, a control method based on observer for integrity against sensor failures is proposed. The state observer of the system is designed according to the time-delay compensation strategy and an augmented mathematic model for the networked control systems based on the state observer is developed, then the cooperative design approach of the controller and the observer is given and the existence conditions of guaranteed cost fault-tolerant control law are testified in terms of the Lyapunov stability theory combined with bilinear matrix inequalities. Furthermore, the designs for fault-tolerant control law and the state observer are presented.

In this work, we focus on monitoring and reconfiguration of an Adaptive Model Reference (MRA) Fault-Tolerant Control (FTC) for large-scale system. This particular class presents an interconnected and networked control system (INCS). Moreover, the system can be decomposed into N-interconnected subsystems communicating with network. Then the global output of INCS and one or more outputs of N-interconnected and networked control subsystems are attacked by sensor faults. Therefore, an active Fault-Tolerant (FT) approach, say the model reference adaptive control of linear systems, is used in order to guarantee not only the stability of an overall INCS globally, but also all local stabilities of N-networked control subsystems with strong interactions, delay and additive faults. Moreover, two architectures: centralized and decentralized adaptive controllers are designed to compensate the sensor faults for different internal structures of systems which are subject of this paper. The law adaptations which make the different faulty systems stable are given. A simulation example of an overall INCS consisting of three interconnected and networked control subsystems and involving stabilization of unstable steady-states is used to demonstrate the efficiency of the proposed approach.

The problem of integrity against sensor failures for the nonlinear networked control systems in which the plant can be described by T-S fuzzy models is studied based on state observer. Assuming that the time-delay is less than one sampling period, the system is modeled as a discrete time T-S fuzzy model with parametrical uncertainties. Based on the model, the fuzzy state observe is designed and according to possible sensor failures, an augmented mathematic model for the systems based on the fuzzy state observer is developed. Then the sufficient stability condition of integrity against sensor failures is given and the designs for fuzzy fault-tolerant controller and fuzzy observer are presented by using the theory of fuzzy control and the approach of Matrix Inequalities.

Analysis of authentication time in challenge-response protocol has been presented here. The protocol has been used in a prototype Networked Control System (NCS) with multiple Plant Control Units (PCU) and Supervisory Control Unit (SCU). The units are programmed in IEC 61131-3 compliant CPDev (Control Program Developer) environment. Global variable manager is used to share common data across the network. The paper presents theoretical estimation of the handshake time during authentication between SCU and PCU. Experiments have been carried out to compare the estimations with a real application.

This work concerns the observer-based control of a remote, master-slave system through the Internet network. This communication link introduces variable, asymmetric and unpredictable delays. The data-sampling effects are also taken into account, even in the aperiodic case. Previous strategies were requiring additional buffers, allowing the delay to become constant but greater and that the slave and the master share the same clock. In this article, these assumptions are not longer required. Thanks to an adequate Lyapunov-Krasovskii functional, the present result uses the information as soon as received. The proposed LMI ensure the asymptotic stability of the global closed loop system. The maximum admissive synchronization error is also computed. The last part of the paper provides an example where the slave is a second-order system.

According to stability theory of fractional-order linear systems, we can obtain any desired stability state from fractional-order chaotic system via linear feedback control. The condition of any desired stability fixed point is established theoretically rigorous. The control parameters are irrelative with stability fixed point.

This paper investigates the problem of robust state feedback H ∞ control for a class of uncertain discrete-time fuzzy systems with time-delays. The state–space Takagi–Sugeno fuzzy model with time delays and norm-bounded parameter uncertainties is adopted. A state feedback controller is designed via the networked control systems(NCSs) theory. The robust controller gain matrices are obtained by solving a set of linear matrix inequalities (LMIs). Sufficient condition for robust stability with H ∞ performance is obtained. Simulation results show that the proposed method is effective.

The utilization of wireless sensor networks in industrial environments poses issues related to performance control. We consider a networked system composed of multiple wireless sensor networks (WSN) that are plugged into a cabled Networked Control System (NCS) made of middleware computers and control stations. The challenge that we faced was to provide predictable end-to-end latency expectations in those settings, as opposed to the problem of predicting latencies within a WSN only. We consider a deployment with multiple small-sized schedule-based WSN sub-networks and the NCS. The approach accounts for details such as de-synch issues that are to be expected in the heterogeneous context. Experimental results show actual latencies and confront them with predictions in a testbed deployment.

Through the analysis of the existing multi-motor control scheme, proposed a multi-motor control system program constituted by the PC ,Siemens PLC, inverter, induction motor etc, designed the overall control system; through the analysis and the characteristics of multi-motor synchronous control and the fuzzy PID control to determine the synchronization control scheme, proposed a control strategy for multi-motor synchronization based on Fuzzy PID compensator, Given a design method of synchronization control based on fuzzy PID compensation algorithm .

This paper is concerned with the adaptive control problem for a class of strict-feedback nonlinear systems, in which unknown virtual control gain function is the main feature. Based on the neural network approximate ability and backstepping control design technique, adaptive neural network based dynamic surface control technique is developed. The advantage is that it does not require priori knowledge of virtual control gain function sign, which is usually demanded in many designs. At the same time, by dynamic surface control scheme, the explosion of computation is circumvented. The control performance of closed-loop systems is improved by adaptive modifying the estimated error upper bound. By theoretical analysis, the signals of closed-loop systems are globally ultimately bounded and the control error converges to a small residual set around the origin.

In this paper, we introduce a new twin support vector regression (TSVR) algorithm, which estimates an unknown function by approaching its up and lower boundary, the ending function is obtained by the mean of the two function. For the class of nonlinear systems composed by linear and nonlinear parts, we use TSVR with a wavelet kernel to estimate the unknown nonlinear part in the original system and to counteract it, and then a state feedback control is carried out to realize a close loop control for the compensated system. Simulation results show that the TSVR with the wavelet kernel has good approaching ability and generalization. The whole close loop system with a state feedback control is stable when the compensating errors satisfy certain conditions.

In paper considered a new type of a feedback that further used for design of control system.

Focusing on the influence made by the time-delay of networked control systems to the system performance and the problems that we are unable to obtain controlled object with all state information in industrial field, a new algorithm to compensate the bad effect caused by the network time-delay is proposed based on the grey prediction method to predict the output of the controlled object at future time. Finally simulate the algorithm by using the TRUETIME toolbox. The result demonstrates that the compensatory strategy in this paper can improve the system performance.

A new adaptive sliding mode control algorithm, based on the T-S fuzzy model, is proposed to deal with the problems of uncertainty and disturbances in networked control system (NCS) . There is variable time delay occurs between controller and actuator in the NCS. Firstly, Choosing the time delay as premise variables of the fuzzy system, the system with control time delay is transformed into the one without time delay based on the fuzzy fusion technology. And then, the global sliding surface is designed by the parallel distributed compensation technique. Adaptive reaching law and disturbances prediction methods are researched. Finally, with a certain variable time delay, the simulation results about DC motor illustrate that the proposed scheme is effective.

This paper proposes a networked multi-agent system based on the real-time Ethernet. The developed system consists of a set of smart networked agents, which are connected by a ring topology through the real-time Ethernet. Each networked agent is designed to realize motion control tasks and real-time communication capabilities using digital signal processor and field-programmable gate array technologies. Furthermore, a real-time communication protocol is proposed to cope with the non-deterministic problem of Ethernet. Then, time delays caused by data processing and message transmission are analyzed. A platform is built to evaluate the capabilities of the developed networked multi-agent system. The experimental results demonstrate that the presented system achieves good performance in terms of real-time communication and servo-control performance.

Minimum step control system includes a pattern control system and no pattern control system, it belongs to one of the discrete control system, which aims to enter in the 3 typical digital controller is designed under the system and take the minimum and limited the number of end Control process, and do not in the sampling error of the moment, so take control of the minimum number of control system design in the design of this controller design is an important part of the design. In the digital control system which, in the complex plane Z domain to achieve a stable, non-error control can be achieved.

Networked Control System of Controllable Pitch Propeller (CPP) is the subsystem of ship’s propulsion system. It influences mostly ship motion, so it’s important to study pitch’s modeling and controlling in order to improve ship’s seaworthiness. Along with the better requests of response speed and maneuverability in ship’s propulsion system, it has been developed from traditional control system to distributed networked control system, while the way of networked control has inevitably caused indefinite network delay. The networked controller has been designed based on the combination of Support Vector Machine, Generalized Predictive Control and Queuing Strategy. It is shown by the study case that the algorithm could effectively compensate the influence of network delay and the networked control system posses of better performances of stability and robustness.

This paper deals with the new approach in the design of hard real-time control applications where the control requirements as well as computing and communication constraints should be jointly taken into account to design a control application. Resource distribution and limitation, safety requirements and autonomy lead to the need of the so called co-design, where the integral problem of the design of the control structure, algorithm and its implementation should be tackled together. Along these lines, after a motivation, the interlacing between both design issues is analyzed and new concepts and architectures are proposed.

In this paper, under a framework of Networked two-layer Learning Control Systems (NLCSs), optimal network scheduling is studied. Multi networked feedback control loops called subsystems in a NLCS share common communication media and therefore there is a competition for available bandwidth and data rate. A non-cooperative game(NG) model is first formulated for the problem studied. The existence and uniqueness of Nash Equilibrium point is proved. Subsequently, the utility function of subsystems is designed, taking account of both transmission data rate and control sampling period according to the feature of scheduling pattern and network control. Following this, a quantum-inspired weight adaptive particle swarm optimization algorithm is developed to obtain an optimal solution. Simulation results presented in the paper have demonstrated the effectiveness of the proposed theoretical approach and the algorithm developed.

A control system is a device or set of devices to manage, command, direct or regulate the behavior of other devices or systems. The trend in most systems is that they are connected through the Internet. Traditional Supervisory Control and Data Acquisition Systems (SCADA) is connected only in a limited private network Since the internet Supervisory Control and Data Acquisition Systems (SCADA) facility has brought a lot of advantages in terms of control, data viewing and generation. Along with these advantages, are security issues regarding web SCADA, operators are pushed to connect Control Systems through the internet. Because of this, many issues regarding security surfaced. In this paper, we discuss web SCADA and the issues regarding security. As a countermeasure, a web SCADA security solution using crossed-crypto-scheme is proposed to be used in the communication of SCADA components.

Real-time Industrial Ethernet will become the development trend of the robot control system. The paper describes main methods how to use industrial Ethernet for robot control system, put forwards some ideas to get a good real-time and low-jitter validation of the robot control system from the following six aspects: bus topology architecture, clock synchronization technology, switching technology, delay prediction algorithm, UDP protocol improving, prediction and compensation control. It gives a timestamp based predictive robot network control system model which combines the technology of clock synchronization, state estimation, delay prediction, predictive control, and the robotics network control system is simulated with Matlab/Simulink and Truetime.