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This paper puts forward a novel multi-rate sampled-data fault-tolerant control strategy for quadrotor unmanned aerial vehicle. By constructing a loop-based Lyapunov functional, stability criteria of the system under aperiodic sampled-data framework is given. Fixing the sampled-data period under velocity and position control, this paper obtains a larger sampled-data period under attitude control than existing literature. An adaptive fault-tolerant control scheme is introduced to ensure steady-state operation in the presence of actuator faults. Furthermore, a multi-rate sampled-data controller solution method is proposed to address the actuator fault problem, enabling the stability of the system under the controllers with normal and uncertain gains. Simulation results using a quadrotor model validate the reliability of the planned fault-tolerant control scheme, ensuring stability even at very low sampled-data frequencies. Through comparative analysis, it is proved that the designed controller enables precise hovering at the desired position, regardless of the presence or absence of actuator faults. [ABSTRACT FROM AUTHOR]

In this paper, the stabilization problem of Takagi–Sugeno (T–S) fuzzy system with input constraints is investigated via a membership function-dependent Lyapunov function (MFDLF). First of all, a membership function-dependent sector condition is adopted to address the input saturation. Then, the average dwell-time (ADT) switching technique is applied to handle the time derivatives of the membership functions, which significantly reduces the conservativeness of the results. Next, on the basis of Lyapunov stability tool, the necessary conditions for the exponential stability are proposed under a non-PDC fuzzy control scheme. Furthermore, the polynomial membership function-dependent matrices are introduced, which achieves the extension of the linear switching to quadratic switching, and further relaxes the conditions. Finally, numerical simulation examples are given for verification. [ABSTRACT FROM AUTHOR]

This paper investigates the secure defense control problem for memristive recurrent neural networks (MRNNs) under denial-of-service (DoS) attacks. Based on quantizer and logical processor techniques, a new secure defense control strategy is designed to maintain the performance of MRNNs subject to DoS attacks. The secure defense control strategy can not only effectively capture information about the dwell time of each DoS attack, but also can effectively reduce the amount of data to be transmitted and save communication resources. By constructing a Lyapunov–Krasovskii functional that depends on sampled information at t k and t k + 1 , some new stability criteria are derived for MRNNs under DoS attacks. By solving a set of LMIs, the control gain of the quantized sampled-data controller can be obtained. Thus, the corresponding secure quantized sampled-data controller is designed for MRNNs under DoS attacks. When there is no quantizer, the secure defense control problem for MRNNs under DoS attacks is also studied. Two numerical examples are given to confirm the effectiveness of the main results. [ABSTRACT FROM AUTHOR]

The mixed planting, as one of the diversification strategies, provides the substitute for many costly inputs, such as fertilizers, pesticides, imported pollinators and irrigation. However, the lack of the farming technology and the expansion of the farming scale have resulted in extremely mismatch between desired yield and manpower. This paper considers groups of agents orderly moving into precise regions, which is suitable for simultaneously planting of different crops. The hierarchical containment control strategy with group-aggregation behavior is proposed under the transformed three-layer topology. Particularly, the dynamic hierarchical containment control protocol is designed such that a novel group-aggregation cooperation in the convex hull can be achieved. A new coupling strength coefficient based on the transformed three-layer topology is defined in the proposed control protocol. Finally, two examples are provided to demonstrate the effectiveness of the proposed dynamic hierarchical containment control protocol for agricultural settings. [ABSTRACT FROM AUTHOR]

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Stability and L 2 -gain control for positive Takagi–Sugeno (T–S) fuzzy systems are further studied in this brief paper. First, considering that the system states are positive, some sufficient conditions of exponential asymptotic stability are obtained by applying a copositive Lyapunov function with membership-function-dependent (MFD) Lyapunov matrices. Based on a preset switching rule, the conditions are expressed as linear matrix inequalities by eliminating the nonconvex factors due to the time derivative of MFD Lyapunov matrices. Then, stability is extended to stabilization by designing a switching controller with time-varying controller gains such that the L 2 -gain performance requirements are satisfied. In addition, a quadratic switching strategy is established to further reduce conservativeness. Finally, the applicability and validity of the theoretical results are validated by two examples. [ABSTRACT FROM AUTHOR]

Considering limited system configurations and communication network bandwidths, this paper proposes two fully distributed event-triggered control schemes, namely synchronous and asynchronous communication, to solve the optimal consensus problem of linear multiagent systems (MASs) with Markovian switching topologies. The concept here is to design a novel composite dynamic event-triggered mechanism for each agent (using the information of all neighbors and one of them), based on which two fully distributed event-triggered protocols are designed to reach consensus and minimize a global convex team performance function. The effectiveness of the proposed control schemes is analyzed theoretically, that is, the optimal consensus problem can be realized, and the MAS does not exhibit Zeno behavior. Compared with existing optimal consensus results, the outstanding advantage of the proposed schemes is that a fully distributed asynchronous event-triggered communication scheme is designed, which fills the gap of optimal consensus results in this respect. [ABSTRACT FROM AUTHOR]

This paper is dedicated to dealing with the sampled measurement-based robust impulsive filter design problem for delayed Lur'e implicit hybrid systems via free-weighting matrix approach. Stochastic admissibility and H ∞ performance index for the implicit impulsive filtering error system are ensured based on a holistic impulse-time-dependent Lyapunov–Krasovskii functional, which embodies the impulse instants, time-varying delays and Markovian jump modes. The effect of sampled measurement output on the impulsive filter is considered, where the sampling moments are corresponding to the impulse instants. By applying the improved free-weighting matrix technique, the derivative of time-varying delay in implicit system states is no longer subject to the least upper bound 1. A set of linear matrix inequalities are applied to construe designing criterion for the desired mode-dependent implicit impulsive filter. The practicality of the developed approach is verified by nonlinear RC circuit. [ABSTRACT FROM AUTHOR]

This article considers the event-based security control problem for an interconnected system with Markovian switching topologies, where the Markovian process governs the switching of the communication topologies. Considering the effect of transmission constraints on control design, a Bernoulli-distributed variable is utilized to formulate the random network attacks. A sampling-data-based event-triggered communication mechanism is presented to decrease unnecessary transmission, where the average data-releasing rate can be decreased greatly. Considering the effects of deception attacks and event-triggered mechanism simultaneously, an observer-based switched control system model is established. By combining this new model and employing the proper Lyapunov–Krasovskii functional, some sufficient criterions are derived such that the closed-loop error system is exponentially mean-square stable with the desired disturbance attenuation, and the controller and observer gain matrices will be tackled simultaneously via the solution of linear matrix inequalities. Finally, this article employs a simulation example to verify the availability of proposed methods. [ABSTRACT FROM AUTHOR]

This research discusses the issue of timer-dependent Lyapunov–Krasovskii functional-based H ∞ impulsive filtering for delayed implicit impulsive Markovian jump systems. A more holistic stochastic timer-dependent Lyapunov–Krasovskii functional featured with time delays, Markovian jump modes and impulse instants information is developed, which lays a solid foundation for the result that the implicit impulsive filtering error system meets stochastic admissibility and specified H ∞ performance index. By applying singular value decomposition method, the internal impulse-freeness and regularity of implicit impulsive filtering error system are realized. Novel sufficient conditions for stochastic admissibility and the realization of mode-dependent implicit impulsive filter are constructed in terms of linear matrix inequalities. Impulsive operator is successfully extended to R n × n , which overcomes the limitation of the one-dimensional impulsive operator and makes the theoretical proposed in this paper more generalizable. The OCCP is offered to illustrate the practicality of the presented approach. [ABSTRACT FROM AUTHOR]

In this paper, we study the synchronization control problem for a class of discrete-time complex dynamical networks (CDNs) under an event-triggered mechanism (ETM). First, a discrete-time distributed periodic ETM is developed based on communication measurement. Under this mechanism, the signal is sampled in a periodic manner, but whether the control signal is updated or not depends on the pre-designed triggering condition. The sampling signal is designed as the communication measurement calculated by both state feedback and inner communication among nodes. Compared with the existing discrete-time ETMs, this method considers the topology connection among network nodes and avoids the continuous measurement of signals. Therefore, this mechanism effectively saves communication resources and reduces the waste of computing resources. Second, in order to analyze the serrated constraint caused by the periodic sampling error, a piecewise Lyapunov function is constructed. Third, under the distributed periodic ETM, sufficient conditions are derived for bounded synchronization of discrete-time CDNs with time-varying delay. Finally, a simulation example verifies the effectiveness and accuracy of the conclusion. [ABSTRACT FROM AUTHOR]

The work deals with these issues of stochastic finite-time boundedness (SFTB), reachable set estimation with input-output finite-time mean square stabilization (IO-FTMSS) for multiple state delayed semi-Markovian jump models subject to uncertainties, stochastic process as well as input constraint. There are few attempts to perform related studies. Firstly, a nonlinear passive control mechanism is designed. Then, a closed-loop model could be acquired. Through stochastic Lyapunov function, these problems of SFTB, reachable set estimation with IO-FTMSS could be solved. In addition, these stability conditions are provided in the framework of linear matrix inequalities. These controller gain matrices, meanwhile, can be derived. At last, this availability of this described strategy can be proved through one simulation. [ABSTRACT FROM AUTHOR]

In this paper, the fault-tolerant bipartite output regulation problem of linear multi-agent systems with two antagonistic subgroups and loss-of-effectiveness actuator faults has been solved by utilizing the output regulation theory. The aim of our study is to design a fault-tolerant controller such that bipartite tracking for the output of exosystem (also seen as the leader) in the presence of actuator faults can be achieved under a directed signed graph, where both collaboration and competition coexist in a multi-agent environment. Firstly, a simultaneous state and fault estimator is designed based upon local output estimation errors such that loss of actuator effectiveness of all followers can be accurately compensated. Then, a distributed adaptive exosystem observer is provided to obtain the information of exosystem since not all followers can directly access exosystem. By using the estimations of state, fault and exosystem, a new cooperative fault-tolerant bipartite output regulation framework with competitive interactions is eventually presented. Finally, we provide a numerical example to demonstrate the effectiveness of the designed fault-tolerant control law. [ABSTRACT FROM AUTHOR]