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This paper investigates the robust containment control problem of multiagent systems with heterogeneous uncertainty and nonlinearity while the nonlinear parts have to satisfy the Lipschitz condition. In this paper, both input time-delay and data transmission time-delay between the agents are considered simultaneously and communication topology of the multiagent systems may switch in the steady-state condition. Under the mentioned conditions, the objective of this paper is to make all the followers’ states converge to the convex hull shaped by the leaders’ states with an expected exponential rate. To this end, an appropriate smooth protocol is proposed. Then, a Lyapunov–Krasovskii functional composed of five terms is proposed and the stability condition is denoted by two linear matrix inequalities (LMIs). In addition to the stability assurance, solving the LMIs would obtain the suitable gains for the protocol. Finally, some numerical simulations are given to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

This paper is concerned with the consensus problem of general linear dynamic multiagent systems with stochastic sampling. In this paper, the sampling intervals randomly switch between two different values. The communication topology between agents is fixed and directed. Full- and reduced-order observers are designed based on neighbor agents’ relative output information. The algorithms to construct such observers are also provided. By using the estimated states of the agents, the observer-based consensus protocol with stochastic sampling are presented. Sufficient conditions to ensure consensus in mean square are derived by using Lyapunov stability theory. Finally, simulations are given to examine the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

This paper is concerned with the event-triggered finite-time control problem for networked switched linear systems by using an asynchronous switching scheme. Not only the problem of finite-time boundedness, but also the problem of input-output finite-time stability is considered in this paper. Compared with the existing event-triggered results of the switched systems, a new type of event-triggered condition is proposed. Sufficient conditions are established to guarantee the event-based asynchronous closed-loop systems are both finite-time bounded and input-output finite-time stable. A set of event-triggered finite-time bounded and input-output finite-time stabilizing controllers are designed under the asynchronous control scheme. It is revealed that the triggered thresholds determine the number of sampling points transmitted to the controller, and the smaller triggered parameters indicate the less-sampled data needed to be transmitted to the controller under the event-triggered scheme. Finally, a boost converter circuit is applied to bring out the advantages of the proposed control scheme. [ABSTRACT FROM AUTHOR]

In this paper, the stability problem of delayed neural networks is investigated by adopting some switching methods. First, the delay interval is divided into many smaller variable intervals, and when the smaller variable interval is regarded as a mode of the delay, delayed neural networks are modeled as switched systems. Then, by using some switching methods, less conservative stability criteria are derived to ensure the stability of delayed neural networks. Finally, one example is provided to show the effectiveness of the obtained criteria. [ABSTRACT FROM AUTHOR]

This paper proposes a unified framework to design sliding-mode control for stabilization of delayed memristive neural networks (DMNNs) with external disturbances. Under the presented framework, finite-time stabilization, and fixed-time stabilization of the controlled DMNNs can be, respectively, obtained by choosing different values for a specific control parameter. It is proved that the system responses can be made reaching the designed sliding-mode surface in finite and fixed time, and then stay on it. Moreover, it also illustrates that the inevitable external disturbances can be rejected by the designed sliding-mode control. Finally, the efficiency and superiority of the obtained main results are verified by comparisons with related works and numerical simulations. [ABSTRACT FROM AUTHOR]

This paper considers the problems on the mean square exponential synchronization and the almost surely exponential synchronization for neutral stochastic dynamical delay networks with Markovian switching via the single pinning impulsive control. By using a unified approach incorporating the concept of average impulsive interval and Lyapunov function, and the Borel–Cantelli lemma, two criteria on the mean square exponential stability and the almost surely exponential stability for impulsive neutral stochastic delay systems with Markovian switching are derived. It is shown that the impulsive control with a suitable impulsive strength can stochastically stabilize the underlying systems. With the symmetry and irreducibility of the switching topologies, and the obtained stochastic stability criteria, sufficient conditions are derived to determine the mean square exponential synchronization of the underlaying networks via the single pinning impulsive controller, which are given with algebraic inequalities and ${\mathcal {M}}$ -matrix. The almost surely exponential synchronization is also analyzed. Two examples are given to verify the validity of the theoretic results presented. [ABSTRACT FROM AUTHOR]

This paper is concerned with the consensus issue for a class of multiagent systems with Markovian switching topology under aperiodic sampled data measurements. By constructing a novel piecewise stochastic Lyapunov-Krasovskii functional, some novel conditions with less conservative are established such that the consensus is achieved in the mean square sense. In contrast to some previous publications, the sample period is no longer fixed and the transition probability matrix of Markovian switching topology is uncertain. This issue which is of practical and theoretical significance is further investigated when the sampled data controller of each agent is suffered from distinct time-varying input delay. Quite different with the related studies, a maximally allowable input delay upper bound is replaced by the permissible input delay interval. Furthermore, the corresponding consensus is elegantly obtained in terms of linear matrix inequalities. Finally, the effectiveness and practicability of our consensus criteria are well illustrated by the numerical examples. [ABSTRACT FROM AUTHOR]

This paper investigates a stabilization problem for linear systems subject to saturation and time-varying delays in the control input, where the delay takes both large and small values in an alternating manner. Based on the delay values, the considered system is described by a switched system including a stabilizable subsystem and an unstabilizable subsystem. By using Lyapunov–Krasovskii functional method, a time-dependent switching rule orchestrating the proposed controllers is established to guarantee the regional stabilization of the closed-loop system. To obtain a domain of attraction as large as possible, an optimization problem is formulated in the form of linear matrix inequalities. Numerical examples and simulations are provided to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper proposes a guaranteed cost control method for uncertain networked control systems with a hybrid communication scheme. First, a hybrid communication scheme including time-triggered control and periodic event-triggered control (ETC) is presented for the system under consideration. The major features of the proposed scheme include three aspects: 1) instead of a fixed switching process, the switching between two triggering methods is stochastic satisfying Bernoulli distribution; 2) the condition of ETC utilizes a more recently transmission data packet, which results in reducing the transmission frequency of sampled data than some existing ones; and 3) Zeno phenomenon can be excluded since the minimum interevent time is implicity denoted by the sampling period. Second, the closed-loop system subject to the hybrid communication scheme and network-induced delay is modeled as an uncertain stochastic system with an interval time-varying delay. Two theorems are presented for the robustly mean-square stability and guaranteed cost controller design of the derived system. Then, a minimization problem is proposed to optimize the upper bound of cost function, in which the trigger parameters and feedback gain can be designed simultaneously. Finally, the effectiveness of the proposed method is demonstrated through a practical inverted pendulum on a cart. [ABSTRACT FROM AUTHOR]

This paper considers the problem of asynchronous ${H}_{{\infty }}$ control for networked Markovian jump systems subject to probabilistic packet dropouts and communication delays in the measurement channel. A new dynamic output-feedback-based asynchronous controller is proposed wherein the dynamic output-feedback controller modes need not synchronize with the system modes. By utilizing results from stochastic Lyapunov–Krasovskii stability theory, sufficient conditions in terms of matrix inequalities are derived such that the closed-loop networked Markovian jump system is stochastically stable and achieves the prescribed ${H}_{{\infty }}$ performance. Using the Schur complement technique and under the assumption that the input matrix is full rank, the sufficient condition is reduced to a linear matrix inequality and the dynamic output-feedback-based asynchronous controller is synthesized. A detailed numerical example with simulation results are presented to evaluate the proposed controller design scheme. [ABSTRACT FROM AUTHOR]

This paper investigates a problem of stability analysis for a class of nonlinear systems with a time-varying delay taking both large and small values in an alternating manner. This problem is a delay-dependent stability analysis one but it shares some features with delay-independent ones. Hence, traditional stability analysis techniques for systems with delay are not applicable. By building upon our previous works, we first introduce the concept of delay-hybrid-dependent stability, which characterizes the delays described above. The considered system is first represented as a system with a switched delay. Then by using switching techniques and Lyapunov–Krasovskii functionals (LKFs), a new stability criterion is developed. Next, in the linear context, it is shown how the needed LKFs can be constructed by developing an original design of LKFs. [ABSTRACT FROM AUTHOR]

This paper investigates the cooperative stabilization problem for a class of linear switched systems under asynchronous switching. Based on a novel class of switching signals which prevail over the traditional average dwell time scheme, a sufficient condition of global asymptotic stability is proposed for the considered system. Unlike the existing results, the provided condition permits the Lyapunov-like function to increase not only in the period of mode-identifying process but also in normal-working period with matched controller. Compensating the increment by an increased decrement, the proposed approach can guarantee the decrease of the Lyapunov-like function from a whole perspective. Moreover, the solvability condition is established as well to obtain the gains for corresponding controllers. Finally, a simulation example is provided to verify the validity of the presented method. [ABSTRACT FROM AUTHOR]

This paper addresses the adaptive tracking problem for a class of uncertain switched stochastic strict-feedback nonlinear systems with both sector-bounded quantization input and unknown time-varying delays under arbitrary switching. Major design difficulties for such systems, in which all the time-varying delays absolutely depend on the subsystem number, come from finding a common Lyapunov function (CLF) for all subsystems and dealing with the sector-bounded quantization error. The Lyapunov–Razumikhin method is employed to construct a suitable CLF for all subsystems and relax the restrictions on the time-varying delays. Moreover, some new techniques are presented to overcome the difficulty from the sector-bounded quantization error. With the application of backstepping technique, variable separation technique and fuzzy logic system approximation, a common adaptive tracking control scheme containing only one adaptive parameter is proposed for this class of systems. The derived quantized control scheme ensures that the tracking error remains in a small neighborhood of the origin via the appropriate adjustment of design parameters while all the signals in closed loop system are bounded in probability. Finally, two simulation examples are provided to illustrate the feasibility and applicability of the proposed control design. [ABSTRACT FROM AUTHOR]

This paper deals with event-triggered H∞ filtering problem for switched continuous-time systems with quantization. A multiple periodic sampling-based event-triggering strategy is adopted to select those “necessary” sampled signals to be transmitted. As a result, the amount of communication and the frequency of signal updates can be reduced significantly. Regarding the nonideal communication network, we consider network-induced delays and packet disorders, which are common during packet transmission through networks. In order to cope with packet disorders, an active packet loss approach is introduced. As such, a new time-delay system model is established, by which the filtering error system is modeled as a switched system with an interval time-varying delay. Then, by employing piecewise Lyapunov functional method and average dwell time technique, some criteria are derived to ensure that the filtering error system can achieve a prescribed level of $H_\infty $ performance. Moreover, the relationship between switching instants and the data updating instants in filter is discussed in detail, and the filter gains and event-triggering parameters can be jointly designed in terms of solutions to some linear matrix inequalities. Finally, numerical simulation is provided to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper addresses a distributed estimator design problem for linear systems deployed over sensor networks within a multiple communication channels (MCCs) framework. A practical scenario is taken into account such that the channel used for communication can be switched and the switching is governed by a Markov chain. With the existence of communicational imperfections and external disturbances, an estimation algorithm is proposed such that the developed distributed estimators are able to give accurate state estimates against the channel switching phenomenon. The distributed estimation framework is applied to a chemical process to illustrate the effectiveness of the proposed methodology and the superiority of the MCCs framework featured by channel switching. [ABSTRACT FROM AUTHOR]

This paper is concerned with the problem of reliable switched controller design for a class of discrete-time Takagi–Sugeno fuzzy systems with randomly occurring infinite-distributed delays and quantization as well as actuator failures. A random Bernoulli process is used to describe the stochastic infinite-distributed delays. Due to limited communication capacity, the control signal is quantized before being transmitted to the actuator by the logarithmic quantizer. We apply the switching mechanisms to categorize the stochastic behavior of actuator faults. Based on the parallel distributed compensation, the switched feedback controller is designed. By the fuzzy-basis-dependent Lyapunov functional approach, sufficient conditions are obtained to ensure that the resulting closed-loop system is exponentially stable in the mean-square sense with a given l {2} - l {\infty } performance index. Then, a numerical example is presented to demonstrate the effectiveness of the proposed new design method. [ABSTRACT FROM AUTHOR]

This paper develops a finite-time control approach for nonlinear teleoperation systems, which is capable of unifying the study of model uncertainties, actuator saturation, and asymmetric time-varying delays in the same framework. First, a novel anti-windup compensator is designed to analyze the effect of actuator saturation. To achieve the finite-time tracking, a nonsmooth generalized switched filter is also investigated. By introducing the anti-windup compensator and the generalized switched filter into the adaptive fuzzy control torque design, a novel finite-time controller is developed. By using the multiple Lypaunov–Krasovskii functionals method, the resulting closed-loop system is state-independent input-to-output practical stable (SIIOpS) and based on this, it is proved to be finite-time SIIOpS. It is shown that the asymptotic convergence of the adaptive estimation errors and the finite-time convergence of the position tracking errors are obtained, whether the robots contact with the human operator/environment or not. Finally, the effectiveness is demonstrated by the simulation results. [ABSTRACT FROM AUTHOR]

Standby redundancy is a design technique that has been widely adopted to enhance system reliability and achieve fault tolerance in many critical applications. In this paper, we consider a 1-out-of-N: G hybrid standby redundant system with unrepairable elements being subject to delayed failure-driven standby mode transfers. Specifically, in the considered system, all the standby elements are initially in a warm standby mode (WSM) but can be transferred to a hot standby mode (HSM) so as to be ready to replace the online operating element when it fails. The WSM to HSM transfer is performed with a fixed time delay after no element resides in HSM either due to the element failure or because the element leaves the HSM to replace the failed online element for operation. A new iterative numerical algorithm is first proposed for evaluating reliability and expected mission cost (relevant to elements’ standby expense, operation expense, as well as mode transfer expense) of the considered hybrid standby system. The algorithm has no restriction on element time-to-failure distribution types. Based on the proposed evaluation algorithm, we further formulate and solve a new optimization problem that finds the optimal delay and optimal sequence of standby elements with the objective to minimize expected mission cost while satisfying a certain level of mission reliability constraint. Examples are presented to demonstrate applications of the proposed methodology. [ABSTRACT FROM AUTHOR]

Switched stochastic systems (SSS) can be used to describe hybrid systems with randomness. However, the languages to describe their discrete switching logic and stochastic dynamic processes are different, and this difference makes their design and analysis hard. This paper proposes a new Petri net model, namely stochastic-differential Petri net (S-DPN), to describe both discrete switching logic, represented by a Markov chain, and stochastic dynamic processes, represented by a set of stochastic differential equations. We then apply a model checking technique to S-DPN to check the correctness of the requirements of SSS. A temperature control system is used to demonstrate the effectiveness of our method. [ABSTRACT FROM PUBLISHER]

This article is concerned with the stochastic stability and $l_{1}$ -gain control of two-dimensional (2-D) positive Markov jump systems (PMJSs) with directional delays based on the Roesser model. First, necessary and sufficient conditions (NSCs) for the stochastic stability of the addressed system are established by constructing a deterministic “equivalent” system and applying a stochastic copositive Lyapunov function. This reveals that the stochastic stability of 2-D PMJSs with delays is affected by the size of directional delays, the transition matrix, and system matrices. Second, the exact $l_{1}$ -gain index is calculated and NSCs in the form of linear programming (LP) are established for the addressed system. Systematic methods for the $l_{1}$ -gain controller design are proposed so that the closed-loop system (CLS) is positive and stochastically stable and has an optimal $l_{1}$ -gain performance, which is achieved using an iterative algorithm and an analytical calculation method for a single-input case. Finally, the potency and accuracy of the theoretical results are verified using two examples. [ABSTRACT FROM AUTHOR]

This article considers the stabilization issue of switched discrete-time positive systems (SDPSs) with delay by using asynchronous control. Combining transition probability (TP) with mode-dependent average dwell time (MDADT), called TP-based MDADT switching, the SDPSs are more practical than classical models with average dwell-time (ADT) switching. With the aid of a co-positive Lyapunov–Krasovskii functional (CLKF), sufficient conditions ensuring the exponential stability almost surely (ES a.s.) of the SDPSs without control is studied, where the mode is not necessary to be stable. After that, a mode-dependent controller with switching delay is designed to stabilize the SDPSs in the case that there are unstable subsystems. An algorithm is provided to design the control gains. It is discovered that the mode in the closed-loop SDPSs is not required to be stable on synchronous and asynchronous switching intervals. Numerical simulations verify the merits of the new results. [ABSTRACT FROM AUTHOR]

The $\mathcal {H}_{\infty }$ state estimation issue for switched delayed inertial neural networks is addressed in this work. A more universal switching law, persistent dwell-time (DT) switching law, is considered here rather than average DT one of which switching frequency among subsystems is strictly limited, or DT one. Concurrently, time delays are inevitable when transmitting information, then taking the time-varying delays into account makes the constructed systems conform well with the actual situations. The main goal in the work is devoted to designing a state estimator to ensure that the state estimation error system is globally uniformly exponentially stable and satisfies a prescribed $\mathcal {H}_{\infty }$ noise attenuation level. A mixed time/mode-dependent Lyapunov–Krasovskii functional matched with the foregoing switching law is introduced. Through utilizing some reasonable inequalities and common matrix operations, some sufficient criteria which guarantee the aforesaid stability and the solvability of the addressed issue are presented. Finally, an illustrative example is provided to present the potentiality and validity of the developed results. [ABSTRACT FROM AUTHOR]

This article addresses the fixed-time average consensus problem of nonlinear multiagent systems (MASs) subject to input delay, external disturbances, and switching topologies. Different from the finite-time convergence, the convergence time of the fixed-time convergence is independent of initial conditions. Then, an event-based control strategy is presented to reach the fixed-time average consensus under switching topologies and intermittent communication. Because the nonlinear dynamics, external disturbances, switching topologies, and triggering condition for intermittent communication are considered, the fixed-time consensus problem is more challenging under the event-based control than under the continuous-time control. Besides, a new measurement error is designed based on the hyperbolic tangent function to avoid Zeno behavior. Furthermore, an improved triggering function is designed to avoid continuous monitoring. Hence, resource consumption is reduced significantly. Finally, the effectiveness of the algorithms is validated by three simulation examples. [ABSTRACT FROM AUTHOR]

Synchronization of a class of drive-response timescale-type nonautonomous proportional-delayed neural networks (TNPNNs) is addressed in this article. The key technique to cope with the proportional term is using comparison principle. By timescale theory, inequality technique, and comparison principle, criteria of synchronization are obtained. The method used in this article is effective to cope with TNPNNs and it is a direct approach as well by eliminating the conventional exponential transformation. The obtained results are verified with three examples. [ABSTRACT FROM AUTHOR]

This article concentrates on finite-time stabilization and energy consumption estimation for nonlinear systems with and without delay. By constructing an appropriate controller and utilizing inequality techniques, sufficient conditions are proposed to guarantee the finite-time stability of the delayed nonlinear system. Furthermore, the energy consumption produced in system controlling is estimated by inequality techniques. Then, we formulate similar results for the delay-free case. Finally, numerical examples are presented to demonstrate the effectiveness of our theoretical results. [ABSTRACT FROM AUTHOR]

This article presents a stabilization achievement for a switched nonlinear time-delay system through output-feedback control under the sampled-data and global senses. An observer with the sampled output measurement is constructed to evaluate the unavailable states, and then a controller formed from the sampled observer states is given. For the stability analysis, a merging virtual switching signal (MVSS) is created to express the asynchronous switching mechanism in the resultant closed-loop system. Through designating a positive-definite function as the Lyapunov function candidate, a proof is conducted to reveal that global stability can be ensured for the considered systems which work under the time-varying delay case and the developed sampled-data controller with a switching restriction. Finally, two examples are provided in this article to indicate the given control strategy usefulness. [ABSTRACT FROM AUTHOR]

This article focuses on the intermittent nonfragile control problem for a class of stochastic neutral-type time-varying delay systems with randomly occurring uncertainties. First, the problem is transformed into the intermittent stabilization problem of generalized systems by variable substitution. Second, based on the dynamic characteristics of the intermittent controlled generalized systems, the time-dependent switching Lyapunov functional is introduced, and the convex combination technique is applied to provide sufficient conditions for the stability of the systems. Then, it is proved that the conditions can be transformed into a feasible solution of a group of linear matrix inequalities. Finally, several numerical examples are provided to verify the effectiveness and advantages of the proposed method. [ABSTRACT FROM AUTHOR]

This article investigates the output regulation problem of probabilistic $k$ -valued logical systems with delays by an intermittent control scheme. Two types of event-triggered control are designed via semi-tensor product (STP) of matrices. According to the algebraic state-space representation of probabilistic $k$ -valued systems with delays, the problem is transformed into the existence of solutions of algebraic equations. Then we obtain the sufficient and necessary condition for the output regulation problem of probabilistic $k$ -valued logical systems with delays. Two types of approaches are given to design the event-triggered control laws. Eventually, two exemplifications are provided to explain the effectiveness and utility of the acquired results. [ABSTRACT FROM AUTHOR]

This note is concerned with bandwidth allocation-based switched dynamic triggering control under DoS attacks and time delay. To prevent DoS attacks from causing open-loop unstable operation of the system with single-channel transmission, we present a primary-redundancy (PR) communication structure on the basis of limited bandwidth allocation; the correlation of communication delay bound between PR channels is introduced. To save the limited bandwidth, we propose a dynamic the event-triggered mechanism (DETM). Then, a switched delay system model is established to describe system dynamic driven by primary channel control, redundancy channel control, and unstable operation under DoS attacks. Further, by using the convex combination method, a switching law for PR channel is designed with the aim of keeping the concealment of the redundancy channel. With the switching law, a criterion of exponential stability is obtained by using piecewise Lyapunov–Krasovskii functional method. A co-design method is proposed to obtain feedback control gains, DETM parameters and switching law parameters. Finally, two simulation examples are illustrated to verify the validness of our proposed method. [ABSTRACT FROM AUTHOR]