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In this paper, we are concerned with the dynamic feedback design for linear systems with input disturbance. We propose a new approach to design dynamic feedback such that the disturbance in the control channel can be compensated effectively. An interesting characteristic about the disturbance robustness of dynamic feedback is found. Thanks to this interesting characteristic, we just need to consider the disturbance-free system to make the dynamic feedback design. This fact is well validated by several dynamic feedback laws proposed in this paper. Our results are available for the regular linear system with harmonic disturbance. Moreover, the stabilization of an unstable heat equation with general periodic disturbance is also investigated. In order to validate the theoretical results visually, some numerical simulations are given to show the effectiveness of the proposed dynamic feedback. [ABSTRACT FROM AUTHOR]

This paper systematically investigates consensus tracking of linear multi-agent systems with disturbances over directed switching topologies. Both state and output feedback H ∞ controllers are jointly synthesized with the triggering mechanism. First, a state-based event-triggered H ∞ controller design for achieving consensus tracking is carried out, which can result in settling the occurrence of disturbances and the reduction of controller updates as well as averting Zeno behavior. Considering the case that only output information of agent is required, an event-triggered H ∞ output feedback controller is then proposed and sufficient condition for the solvability of consensus tracking problem are also derived. Compared with the existing results, the effects of disturbances on directed switching topologies can be tackled when continuous communication and full-state information of the agent are not needed. Numerical simulation are finally conducted to illustrate the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

In this paper, the dynamic event-based resilient consensus control of the multiple networked Euler-Lagrangian (E-L) systems under the Denial of Service (DoS) attacks is considered. Compared with linear cyber-physical systems, nonlinear networked E-L systems are more complex and closer to actual mechanical systems. For the situation where the topology is a strongly connected directed topology, a controller based on a dynamic event-trigger mechanism is designed to achieve consensus control for the networked E-L system in the absence of DoS attacks. Sufficient conditions are presented, which can guarantee the closed-loop system be stable. Then the resilient consensus problem of event-based controllers under energy-constrained DoS attacks is analyzed. The conditions related to the duration and frequency of DoS attacks are given. Zeno behavior is proved does not exist in the proposed control scheme. Finally, some numerical simulation results are given for verifying the theoretical results. [ABSTRACT FROM AUTHOR]

This paper is concerned with the smallest asymptotic bound of solutions to a positive mixed fractional-order inhomogeneous linear system subject to time-varying delays and bounded disturbance. In particular, when its linear part is asymptotically stable and the disturbance is small, we have obtained the smallest bound (as the time is large enough) of the solutions with the arbitrary initial condition. In the case where the assumption that the disturbance converges to 0 as the time t tends to infinity is added, we have shown that every solution of the system tends to the origin. Numerical simulations are finally presented to illustrate the theoretical findings. [ABSTRACT FROM AUTHOR]

This paper presents two stochastic model predictive control methods for linear time-invariant systems subject to unbounded additive uncertainties. The new methods are developed by formulating the chance constraints into deterministic form, which are treated in analogy with robust constraints, by using the probabilistic reachable set. The first one is the time-varying tube-based stochastic model predictive control algorithm, which is designed by employing the time-varying probabilistic reachable sets as tubes. The second one is the constant tube-based stochastic model predictive control algorithm, which is developed by enforcing a constant tightened constraint in the entire prediction horizon. In addition, the soft constraints are proposed to associate with the state initialization in the algorithms to enhance the feasibility. The algorithm feasibility and closed-loop stability results are provided. The efficacy of the approaches is demonstrated by means of numerical simulations. [ABSTRACT FROM AUTHOR]

• The target is considered to be maneuvering. • The terminal acceleration command is constrained to zero without usage of switching logics. • The virtual look angle is constrained during the interception. • The proposed nonlinear guidance law is proved to be near-optimal. • All-aspect interception can be realized. To realize the terminal acceleration constraint for a bias proportional navigation guidance law without usage of switching logics, this paper proposes a modified bias term and presents a terminal acceleration constrained bias proportional navigation guidance law against maneuvering targets. First, a so-called virtual planar coordinates whose origin is attached to the point mass of the target is built, so that the original maneuvering target is transformed to a virtual stationary target. On this basis, the common structure of bias proportional navigation guidance law is presented. To realize the terminal acceleration constraint, a modified bias term related to the relative distance between target and missile is used to improve the bias proportional navigation guidance law. With the virtual look angle and the line-of-sight angle constrained, the proposed modified bias proportional navigation guidance law can intercept the maneuvering targets in a desired attack angle. Comparisons with the optimal guidance law in the linear system are carried out, and the proposed law is proved to be near-optimal. The numerical simulation results demonstrate the all-aspect interception capability of the proposed law against maneuvering targets. [ABSTRACT FROM AUTHOR]

This paper considers the optimal control problems of switched autonomous linear systems and switched non-autonomous linear systems in discrete-time, where the objective is that of minimizing a linear quadratic performance index function or multiple linear quadratic performance index function. The subsystems switching sequence and the number of switchings are free in this paper. By employing an embedding technique, we embed the origin switched autonomous or non-autonomous linear systems into a larger family of systems. Owing to the embedding technique, the optimal control problem of the origin switched linear systems can be relaxed into a traditional optimal control problem for the larger family systems. We thus derive the optimal switching control law and the optimal control input for the bang-bang type optimal solution of the relaxed optimal control problem simultaneously. The optimal solution of the origin switched optimal control problem can be obtained by the bang-bang type optimal solution of the relaxed optimal control problem. Finally, results of numerical simulation examples are given to demonstrate the remarkable effectiveness and superiority of the developed method. [ABSTRACT FROM AUTHOR]

This paper mainly investigates the issue of parameters identification for continuous time fractional order Hammerstein systems. When the commensurate order of linear part in system is prior information, two estimation algorithms are proposed to identify the parameters. Both methods use filters to obtain the derivative of the continuous time signal: one based on the Poisson filter and the other using the auxiliary model to construct the filter. Afterwards, the commensurate order update law is given, which contains the relationship between parameters and orders. In addition, due to the existence of fractional order terms, an irrational item will be introduced, and this paper gives a detailed mathematical derivation to discuss this issue. The effectiveness of proposed methods is demonstrated by the numerical simulations. [ABSTRACT FROM AUTHOR]

This paper is devoted to the dynamic event-triggered consensus problem of general linear multi-agent systems under fixed and switching directed topologies. Two distributed dynamic event-triggered strategies, where internal dynamic variables are involved, are introduced for each agent to achieve consensus asymptotically. Compared with the existing static triggering strategies, the purposed dynamic triggering strategies result in larger inter-execution times and less communication energy among agents. In addition, neither controller updates nor triggering threshold detections require continuous communication in the purposed control strategies. It is also proven that the Zeno behavior is strictly ruled out under fixed and switching directed topologies. Finally, the effectiveness of the theoretical analysis is demonstrated by numerical simulations. [ABSTRACT FROM AUTHOR]

This paper is concerned with the optimal stealthy attack problems of cyber-physical system, which is represented as discrete-time linear systems. It is considered that a deceptive attack assumed to be able to hijack and modify the nominal control signals from the controller-actuator channel with the metric of ϵ -stealthiness. Different from the existing literatures, some optimal attack strategies with objectives such that maintaining a fixed level of stealthiness and achieving the maximized performance degradation are designed under some constraints. It is further derived that the results of ours are more relaxed than some methods proposed before. Finally, some numerical simulations are given to illustrate the validity of the theoretical results. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of state and unknown input estimation for linear discrete-time systems subject to unknown but bounded process disturbance and measurement noise. The existing methods treat this problem based on coordinate transformation, which is complex and may incorporate some conservatism. Unlike the existing methods, we estimate the state and unknown input simultaneously based on an augmented approach. Then a novel observer structure and an L ∞ norm based approach are presented to obtain a tight interval of estimation. The viability and validity of the proposed method are demonstrated by numerical simulations. [ABSTRACT FROM AUTHOR]

This paper studies the cooperative output regulation problem of discrete-time linear multi-agent systems subject to Markov switching topologies.To cope with the problem that some followers cannot directly obtain the state information of the leader and themselves, the distributed state feedback control algorithm and output feedback control algorithm are designed based on the Markov state compensators of the leader and followers, respectively. Then, the corresponding sufficient conditions for solving the cooperative output regulation problem of multi-agent systems with unstable and stable exosystem are proposed, respectively. Finally, numerical simulations are provided to verify the effectiveness of the designed algorithms. [ABSTRACT FROM AUTHOR]

In this paper, the leader-following consensus problem of general linear multi-agent systems without direct access to real-time state is investigated. A novel observer-based event-triggered tracking consensus control scheme is proposed. In the control scheme, a distributed observer is designed to estimate the relative full states, which are used in tracking consensus protocol to achieve overall consensus. And an event-triggered mechanism with estimated state-dependent event condition is adopted to update the control signals so as to reduce unnecessary data communication. Based on the Lyapunov theorem and graph theory, the proposed event-triggered control scheme is proved to implement the tracking consensus when real-time state cannot direct obtain. Moreover, such scheme can exclude Zeno-behavior. Finally, numerical simulations illustrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

• The first study to solve the approximation problem of T-S fuzzy linear singular system for a class nonlinear singular system with derivative of input and the nonlinear singular system exists impulses. • The algorithm that if input-state system is Bounded Impulse-free Item and Separable Impulse Item, it can be approximated by T-S fuzzy singular system with arbitrary accuracy is given. • Considering a practical example (A two-wheel drive robot) and two numerical examples, the effect of algorithm approximation is especially good. In this paper, the approximation problem of T–S fuzzy linear singular system for a class of nonlinear singular system with derivative of input is considered and the nonlinear singular system has impulses. Consider a numerical example and a two-wheel drive robot, the T–S fuzzy singular systems are calculated for original system with derivative of input. According to solvability and steps of solving of the two examples, the results are extended to more generally nonlinear singular system with derivative of input. The theorem and algorithm that are given if input-state system is bounded impulse-free item and separable impulse item, it can be approximated by T–S fuzzy singular system with arbitrary accuracy. Finally, a numerical simulation is carried out to show the consistency with theoretical analysis and illustrate the effectiveness of approximation. [ABSTRACT FROM AUTHOR]

Abstract This paper considers the consensus disturbance rejection problem of networks of linear agents with event-triggered communications in the presence of matched disturbances. Based on the disturbance observer, distributed event-based consensus protocols are proposed and constructed for both the cases of neutrally stable and general linear agents. Under the proposed event-based consensus protocol, it is shown that the consensus errors are asymptotically stable and the Zeno behavior can be excluded. Compared to the previous related works, our main contribution is that the proposed event-based protocol can achieve consensus and meanwhile reject disturbance, without the need of continuous communications among neighboring agents. For the case of neutrally stable agents, the event-based protocol is fully distributed, using only the local information of each agent and its neighbors. Simulation results are presented to illustrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

This paper presents a fixed-time observer for a general class of linear time-delay systems. In contrast to many existing observers, which normally estimate system’s trajectory in an asymptotic fashion, the proposed observer estimates system’s state in a prescribed time. The proposed fixed-time observer is realized by updating the observer in an impulsive manner. Simulation results are also presented to illustrate the convergence behavior of the proposed fixed-time observer. [ABSTRACT FROM AUTHOR]

In this paper, the issues of finite-time extended dissipative analysis and non-fragile control are investigated for a class of uncertain discrete time switched linear systems. Based on average dwell-time approach, sufficient conditions for the finite-time boundedness and finite-time extended dissipative performance of the considered systems are proposed by solving some linear matrix inequalities, where using the concept of extended dissipative, we can solve the H ∞ , L 2 − L ∞ , Passivity and ( Q, S, R )-dissipativity performance in a unified framework. Furthermore, two form of non-fragile state feedback controllers are designed to guarantee that the closed-loop systems satisfy the finite-time extended dissipative performance. Finally, simulation example is given to show the efficiency of the proposed methods. [ABSTRACT FROM AUTHOR]

This paper proposes an approach for constructing and generating chaos from a class of three-dimensional linear switching systems via a heteroclinic loop based on the Shilnikov criterion. First, the existence of a switching rule for the system is derived by utilizing the Shilnikov heteroclinic criterion. Then a general design philosophy and its procedure of switching rule are provided to ensure that the proposed approach is applicable to engineering. Two numerical examples are presented to validate the main principle and the implementability of the scheme. Theoretical analysis and numerical simulation are used to demonstrate the feasibility and effectiveness of developed techniques. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the central finite-dimensional filter for nonlinear polynomial systems with multiplicative noise, that is suboptimal for a given threshold with respect to a modified Bolza–Meyer quadratic criterion including the attenuation control term with the opposite sign. In contrast to the previously obtained results, the paper reduces the original filtering problem to the corresponding optimal H 2 filtering problem, using the technique proposed in . The paper presents the central suboptimal filter for the general case of nonlinear polynomial systems with multiplicative noise, based on the optimal H 2 filter given in . The central suboptimal filter is also derived in a closed finite-dimensional form for third (and less) degree polynomial system states. Numerical simulations are conducted to verify performance of the designed central suboptimal filter for nonlinear polynomial systems against the central suboptimal filters available for polynomial systems with state-independent noise and the corresponding linearized system. [ABSTRACT FROM AUTHOR]

This paper is concerned with the distributed H ∞ - consensus filtering problem for a class of piecewise discrete-time linear systems. Firstly, the modes and their transitions of augmented piecewise linear systems as well as distributed filters are formulated. Also, the structure of augmented distributed filter gains is presented in virtue of the adjacent matrix of sensor networks. Then, a set of sufficient conditions are provided for the distributed filter to ensure that its dynamics is global asymptotically stable with the H ∞ - consensus performance constraint. In addition, the distributed filter gains are obtained with the aid of the convex optimal method. At last, an illustrative simulation is presented to demonstrate the effectiveness and applicability of the proposed distributed filtering algorithm. [ABSTRACT FROM AUTHOR]

Abstract: This paper offers an efficient sliding manifold design method that minimizes the impact of unmatched disturbances onto SM dynamics and system accuracy. System sensitivity upon unmatched constant or slowly varying external disturbance vector is evaluated by the steady-state dependent criterion function. An infinite set of sliding manifolds that minimize the chosen optimization criterion is determined and a way of selecting a manifold out of that set that provides adopted SM dynamics is suggested. The proposed approach has been demonstrated on numerical examples and verified by simulations. [Copyright &y& Elsevier]

Abstract: The multi zone space heating system (MZSH) is an interconnected dynamical system subject to external disturbances and input saturation. In this paper, the problem of temperature control design in MZSH is investigated. The design of decentralized controllers are tackled using an iterative-procedure based on the homotopy method. Numerical simulation are presented and compared with an improved decentralized method based on linear quadratic theory to show the efficacy of the developed approach. [Copyright &y& Elsevier]

Abstract: In this paper, an adaptive risk-sensitive multiple-model filtering method which relaxes the restrictive assumption that risk-sensitive parameter is chosen as a prior is proposed for a class of discrete-time Markov jump linear systems (MJLSs) with uncertain parameters. Some analysis is presented to illustrate the essential effect of the risk sensitivity added into the filtering process and show the intrinsic reasons for the improvement of robustness. Then, a quite useful principle is developed to obtain the risk-sensitive parameter using the measurements in an online fashion. To avoid overregulation under mismatched modes and mitigate the problem of smearing the feature of each model, a minimization mechanism is resorted to. Computer simulations are presented to reveal the effectiveness of our method. [Copyright &y& Elsevier]

Abstract: In this paper, new results are established for generating tracking policies in aggregated production-inventory systems. A dynamic model is developed to characterize the evolution of targeted production, inventory and demand over time and incorporates the inventory, production and demand tracking errors as additional variables. The control variables are managerial decision variables on rate of production and advertisement. The developed model takes the form of linear system with time-varying delay. Tracking policies are then formulated and determined to ensure that the production-inventory tracking model achieves a desirable performance in terms of . Numerical simulation is performed to illustrate the theoretical developments. [ABSTRACT FROM AUTHOR]