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In this study, an adaptive fuzzy decentralized dynamic surface control (DSC) problem is investigated for switched large-scale nonlinear systems with deferred asymmetric and time-varying full-state constraints. Due to the existence of additional general nonlinearities, complicated output interconnections, and full-state constraints, it is difficult to address the above control problem using existing methods. Fuzzy-logic systems are, therefore, utilized to approximate the unknown nonlinear functions, and the DSC technique is adopted to overcome the “curse of dimensionality” problem. A novel fuzzy adaptive decentralized controller design is presented using the proposed convex combination technique. Furthermore, it is proven that under the proposed controller and state-dependent switching law, all states of the closed-loop system are bounded and deferred asymmetric, and the time-varying full-state constraints are strictly obeyed. The simulation results are presented to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

To handle the decentralized fuzzy adaptive outputfeedback fault-tolerant control problem for nonlinear switched large-scale systems with sensor faults and unknown control gains, a decentralized fault-tolerant control (FTC) strategy is proposed. As only the actual outputs are measurable when the sensor faults occur, a novel state observer is designed to estimate unmeasured states and address unknown control gains simultaneously. The unknown nonlinear functions are approximated by fuzzy logic systems. Based on the backstepping technique and the average dwell time method, decentralized FTC controllers are designed. It is proven that all states of the closed-loop system are semiglobal uniformly ultimately bounded and the tracking errors can converge to a small neighborhood of zero. A simulation example is presented to show the effectiveness of the developed strategy. [ABSTRACT FROM AUTHOR]

In this article, the output consensus problem is investigated for a class of switched nonlinear multiagent systems, where denial-of-service attacks and faults are considered in communication channels and agents’ actuators, respectively. The cyber attacks can damage the communication channels, which will cause the consensus performance degradation or even failure to achieve consensus. Compared with the existing results on consensus of multiagent systems under cyber attacks, the agents’ dynamics in this article are described by higher order heterogeneous switched nonlinear systems. The cyber attacks, actuator faults, asynchronous switchings, and the high complexity of the system make the existing consensus algorithms ineffective. A novel control scheme for the output consensus of the multiagent system subject to cyber attacks is proposed. By the graph theory, switched system theory and Lyapunov function method, sufficient conditions are presented to check whether the consensus objective can be achieved. Finally, the effectiveness of the proposed scheme is illustrated by two numerical simulations. [ABSTRACT FROM AUTHOR]

In this article, the distributed fault-tolerant consensus tracking control problem is investigated for a class of nonlinear multiagent systems, where the dynamics of agents are heterogeneous and switched. For the subsystems of each agent, nonlinear terms are not required to satisfy any growth conditions and fuzzy logic systems are employed to approximate unknown functions. In the protocol design, information on the interaction topology and the number of agents cannot be used. Since the underlying multiagent systems are heterogeneous and have switching characteristics, and the topology information is unknown, it is rather difficult to solve the consensus tracking problem using existing algorithms. In this article, a novel distributed consensus tracking protocol is developed. By using the graph theory, Lyapunov functional method and fuzzy logic systems approximation technique, it is proven that the consensus tracking control objective can be achieved for multiagent systems suffering from actuator faults and arbitrary switchings. Finally, to demonstrate the validity of the developed methodology, a numerical simulation is presented. [ABSTRACT FROM AUTHOR]

This article investigates the sampled-data stabilization problem of a class of switched nonlinear systems. All subsystems of the considered system are allowed to be unstabilizable. To relax the restrictions on unknown nonlinear functions in some existing results, we use the nonlinear approximation ability of radial basis function neural networks. Novel mode-dependent adaptive laws and sampled-data control laws are constructed by only using the system states’ information at sampling instants. A novel sampled-data switching condition is derived, which can avoid Zeno behavior effectively. To guarantee that all states of the closed-loop system (CLS) are bounded, a new allowable sampling period is deduced. Finally, we demonstrate the proposed method’s effectiveness through two examples. [ABSTRACT FROM AUTHOR]

This study considers an adaptive neural-network (NN) periodic event-triggered control (PETC) problem for switched nonlinear systems (SNSs). In the system, only the system output is available at sampling instants. A novel adaptive law and a state observer are constructed by using only the sampled system output. A new output-feedback adaptive NN PETC strategy is developed to reduce the usage of communication resources; it includes a controller that only uses event-sampling information and an event-triggering mechanism (ETM) that is only intermittently monitored at sampling instants. The proposed adaptive NN PETC strategy does not need restrictions on nonlinear functions reported in some previous studies. It is proven that all states of the closed-loop system (CLS) are semiglobally uniformly ultimately bounded (SGUUB) under arbitrary switchings by choosing an allowable sampling period. Finally, the proposed scheme is applied to a continuous stirred tank reactor (CSTR) system and a numerical example to verify its effectiveness. [ABSTRACT FROM AUTHOR]

In this article, we investigate the adaptive decentralized output feedback sensor failure compensation control issue of nonlinear switched interconnected systems. A new switched state observer is designed based on the false state information for estimating unmeasured states. To address the challenges incurred by the partial loss of the effectiveness of sensors, a novel adaptive failure compensation mechanism containing error signals is adopted. Mode‐dependent adaptive laws that can explicitly reflect switchings of the system are designed. A decentralized adaptive failure‐tolerant controller is constructed by using backstepping technique. It is proved that the presented scheme can guarantee that the system outputs track the reference signals and all signals in the closed‐loop system are bounded with average dwell time switchings. A practical simulation example is provided to illustrate the effectiveness of the presented scheme. [ABSTRACT FROM AUTHOR]

The adaptive fuzzy finite-time tracking control problem of a class of switched nonlinear systems is investigated in this study. Fuzzy logic systems are introduced to handle the unknown nonlinear terms in the considered system. To overcome the drawback in the recursive design method, a finite-time command filter is employed. By constructing a new state-dependent switching law and adaptive fuzzy control signal, the existing restrictions on subsystems of switched systems are relaxed, all subsystems of the considered system are allowed to be unstabilizable. To avoid the Zeno behavior, a new hysteresis switching law is derived. It is proven that all states of the closed-loop system are bounded in finite time under the proposed fuzzy finite-time control scheme. Additionally, the proposed control method is extended to a class of more general switched large-scale nonlinear systems. Finally, two examples are provided to verify the developed method's effectiveness. [ABSTRACT FROM AUTHOR]

The global output feedback stabilization problem is investigated in this paper via sampled-data control for switched nonlinear systems in the $p$ -normal form. First, a reduced-order state observer is designed. Then, an output feedback sampled-data controller is constructed with the relaxation of some restrictions of switched nonlinear systems. The proposed controller can ensure that all states of the corresponding closed-loop system can converge to the origin. Simulation results are given to show the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

This paper investigates a global practical stabilisation problem of a class of switched nonlinear systems via sampled-data control, where all the subsystems are assumed to be in non-strict feedback form and all the z 0 -subsystems are not required to be input-to-state stable. Since the system states are unmeasurable and the output can only be measured at the sampling instants, an observer is designed to estimate the state. By adopting the multiple Lyapunov function method and the backstepping technique, a virtual controller is constructed, then a sampled-data controller is obtained by discretizing the designed virtual controller. With appropriate choice of a switching law and an allowable sampling period, it is proved that the designed sampled-data controller renders the corresponding closed-loop system to be globally practically stable. Finally, two examples are presented to illustrate effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

In this article, a decentralized output feedback control problem for switched large-scale stochastic nonlinear systems subject to asynchronous switching is considered via sampled-data control. We design a state observer by only using the sampled information. Utilizing the average dwell time method, a sampled-data controller is constructed to ensure that the closed-loop system is globally asymptotically stable in mean square. Two examples are provided to demonstrate the developed strategy’s effectiveness. [ABSTRACT FROM AUTHOR]

In this paper, the global sampled-data control problem has been considered for large-scale switched time-delay nonlinear systems subject to actuator failures. A reduced-order observer is developed to estimate unmeasured states, and a decentralized sampled-data controller is designed with an allowable sampling period. It can be shown that all states of the corresponding closed-loop system are globally uniformly ultimately bounded under arbitrary switchings through the choice of the suitable Lyapunov– Krasoviskii functional. Finally, the validity of the proposed control scheme is verified using an example. [ABSTRACT FROM AUTHOR]

This study investigates the output feedback sampled-data stabilization problem of a class of switched large-scale nonlinear systems with asynchronous switching and dead zones. Since only the system outputs are available at the sampled-data instants, a state observer is constructed to estimate the unmeasured state. To deal with nonlinear interconnections, a new decentralized sampled-data controller is designed. A novel average dwell-time constraint condition is derived to guarantee the considered system's stability in the presence of asynchronous switching. The proposed method's effectiveness is demonstrated by its application to a quadruple-tank process system. [ABSTRACT FROM AUTHOR]

This paper considers the global stabilization problem via sampled-data control for a class of switched nonlinear systems meanwhile taking into account asynchronous switching. First of all, a state feedback sampled-data controller is constructed by backstepping design method. Then, a relationship between the sampling period and the average dwell time is derived, which can guarantee that the closed-loop system is globally asymptotically stable. Finally, two simulation examples are presented to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Summary: This paper investigates a global sampled‐data output feedback stabilization problem for a class of switched stochastic nonlinear systems whose output and system mode are available only at the sampling instants. An observer is designed to estimate the unmeasurable state and thus a sampled‐data controller is constructed with the sampled estimated state. As a distinctive feature, a merging virtual switching signal is introduced to describe the asynchronous switching generated by detecting the system mode via a sampler. By choosing an appropriate piecewise Lyapunov function, it is proved that the proposed sampled‐data controller with allowable sampling period can stabilize the considered switched stochastic nonlinear systems under an average dwell‐time condition. Finally, two simulation results are presented to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, an adaptive iterative learning control (ILC) method is proposed for switched nonlinear continuous-time systems with time-varying parametric uncertainties. First, an iterative learning controller is constructed with a state feedback term in the time domain and an adaptive learning term in the iteration domain. Then a switched nonlinear continuous-discrete two-dimensional (2D) system is built to describe the adaptive ILC system. Multiple 2D Lyapunov functions-based analysis ensures that the 2D system is exponentially stable, and the tracking error will converge to zero in the iteration domain. The design method of the iterative learning controller is obtained by solving a linear matrix inequality. Finally, the efficacy of the proposed controller is demonstrated by the simulation results. [ABSTRACT FROM AUTHOR]

This paper considers the problem of sampled-data adaptive output feedback fuzzy stabilization for switched uncertain nonlinear systems associated with asynchronous switching. A state observer is designed to estimate the unmeasured states and fuzzy logic systems are employed to deal with the unknown nonlinear terms. Sampled-data controller and novel switched adaptive laws are constructed based on the recursive design method and an average dwell time constraint is given to ensure that the closed-loop system is stable. The proposed scheme is employed in a mass–spring–damper system to demonstrate its effectiveness. [ABSTRACT FROM AUTHOR]

This paper investigates the finite-time stabilisation for a class of switched nonlinear systems with state constraints. Some power orders of the system are allowed to be ratios of positive even integers over odd integers. A Barrier Lyapunov function is introduced to guarantee that the state constraint is not violated at any time. Using the convex combination method and a recursive design approach, a state-dependent switching law and state feedback controllers of individual subsystems are constructed such that the closed-loop system is finite-time stable without violation of the state constraint. Two examples are provided to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, an adaptive prescribed performance output-feedback control scheme is proposed for a class of switched nonlinear systems with input saturation. The MT-filters are employed to estimate the unmeasured states and the unknown functions are approximated by the radial basis function neural networks in controller design procedure. It is proved that all the signals in the closed-loop system are semi-globally uniformly ultimately bounded and the tracking error satisfies the prescribed performance. Finally, simulation results are given to illustrate the effectiveness of the proposed approach. [ABSTRACT FROM PUBLISHER]

This paper proposes an adaptive tracking control scheme for a class of non-affine switched stochastic nonlinear systems with unmeasured states and stochastic inverse dynamics. K-filters are used to estimate unmeasured states, and a changing supply function is introduced to deal with stochastic inverse dynamics. By using neural networks, dynamic surface technique and common Lyapunov function method, a controller and adaptive laws are designed for the considered system. The proposed control scheme guarantees that all signals of the closed-loop system are bounded in probability. Finally, a simulation example is presented to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper is concerned with the design of a high-order repetitive control (RC) law for a class of discrete-time linear switched systems with repetition-varying reference trajectories. First, a high-order RC law, which embeds the characteristic of known variation of the reference trajectories, is proposed to the system, and a two-dimensional (2D) model is presented to describe the control and learning actions of the repetitive control system by using the lifting technique. By choosing appropriate multiple Lyapunov–Krasovskii functions, sufficient conditions for asymptotic stability of the 2D system are derived in the form of a set of linear matrix inequalities. Finally, an example is given to illustrate the effectiveness of the proposed results. [ABSTRACT FROM PUBLISHER]

This paper addresses the stabilisation problem for a class of positive switched nonlinear systems under asynchronous switching, which means that the switches between the candidate controllers and the system modes are not synchronous. The continuous and discrete cases are considered respectively. Sufficient conditions are firstly provided for the existence of the asynchronous switching controllers to guarantee the closed-loop system to be positive and exponentially stable, and the corresponding admissible switching signals are presented. As a special case, the stabilisation results for positive switched linear systems under asynchronous switching are provided accordingly. Finally, two numerical examples are given to illustrate the effectiveness of the proposed methods. [ABSTRACT FROM PUBLISHER]

This paper investigates the finite-time output tracking for a class of switched nonlinear systems in p-normal form. Compared with the existing results, the restrictions on power orders of the system are relaxed. Using the convex combination method and the adding a power integrator technique, a state-dependent switching and law, and state feedback controllers of individual subsystems are constructed. It is shown that all states of the closed-loop system are bounded, and the tracking error can converge to a small neighborhood of zero in finite time. An example is provided to show the effectiveness of the proposed method. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper investigates the finite-time stabilization of a class of switched stochastic nonlinear systems in p -normal form, where the power orders of the system are dependent upon the switching signal and the system structure is in non-triangular form. Compared with the existing results, some power orders of the system are allowed to be even. Under suitable assumptions, a state feedback control law with state-dependent switching is designed by using the convex combination method and the adding a power integrator technique. It is shown that the resulting closed-loop system is finite-time stable in probability. Simulation results of a continuously stirred tank reactor (CSTR) system are provided to show the effectiveness and applicability of the proposed method. [ABSTRACT FROM AUTHOR]

This paper studies the problem of stabilising a sampled-data switched linear system by quantised feedback asynchronously switched controllers. The idea of a quantised feedback asynchronously switched control strategy originates in earlier work reflecting actual system characteristic of switching and quantising, respectively. A quantised scheme is designed depending on switching time using dynamic quantiser. When sampling time, system switching time and controller switching time are all not uniform, the proposed switching controllers guarantee the system to be finite-time stable by a piecewise Lyapunov function and the average dwell-time method. Simulation examples are provided to show the effectiveness of the developed results. [ABSTRACT FROM AUTHOR]

This paper investigates the finite-time stabilization of a class of switched stochastic nonlinear systems under arbitrary switching, where each subsystem has a chained integrator with the power r (0 < r < 1). By using the technique of adding a power integrator, a continuous state-feedback controller is constructed, and it is proved that the solution of the closed-loop system is finite-time stable in probability. Two simulation examples are provided to show the effectiveness of the proposed method. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, an adaptive tracking control scheme is proposed for a class of switched nonlinear systems with state and input unmodeled dynamics. The unmodeled dynamics are dealt with by introducing a first-order filter and a dynamic signal. K-filters are used to estimate the unmeasured states, and the dynamic surface control (DSC) technique is employed to construct the controller to avoid the explosion problem of complexity. By choosing an appropriate common Lyapunov function, the boundedness of all closed-loop signals is proved, and the tracking error can converge to a small neighborhood of zero in finite time under arbitrary switchings. Finally, a simulation example is provided to show the feasibility and validity of the proposed method. [ABSTRACT FROM AUTHOR]

This paper investigates the stability and $$L_1$$ -gain control of two-dimensional (2-D) continuous positive switched delayed systems. Firstly, by constructing an appropriate co-positive Lyapunov-Krasovskii functional, a sufficient condition for asymptotical stability of the system under consideration is derived. Secondly, $$L_1$$ -gain performance analysis of the underlying system is investigated. Thirdly, a design methodology for state feedback controller is proposed to ensure that the closed-loop system is asymptotically stable with $$L_1$$ -gain performance. Finally, an example is provided to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper investigates the problems of anti-windup design and l2-gain analysis for a class of discrete-time impulsive switched systems with actuator saturation. Supposing that a set of linear dynamic output controllers have been designed to stabilize such a system without considering its input saturation, we design anti-windup compensation gains to guarantee the stability of the closed-loop system in the presence of saturation. l2-gain performance analysis is also developed. Finally, two examples are given to illustrate the effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]