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In this article, an asynchronous output-feedback controller is proposed for a class of Markovian jump systems (MJSs) with generally bounded transition rates (TRs). Specifically, two cases have been considered, one of which assumes the TR being completely unknown, while the other specifies the TR range. In particular, the designed asynchronous output-feedback controller is independent of the system modes, implying a sustainable controlling behavior against unavailable system modes. It is worth noting that the mode-dependent controller can be treated as a special case of the independent one. Furthermore, the existing conditions of such a controller are acquired in terms of linear matrix inequalities. Finally a practical example, concerning a single-machine infinite-bus power system, is given to confirm the feasibility of the proposed controller. [ABSTRACT FROM AUTHOR]

This article proposes a method on simultaneous estimation of the system fault and sensor fault for a kind of the Markovian jump system with generally uncertain transition rates. In order to estimate these system fault and sensor fault, we first design a novel reduced-order observer, in which the gain matrix can not only decouple the existed unknown input, but also compel the observer error dynamic system to be stable. Then, the existing conditions of the proposed observer are derived in terms of linear matrix inequalities, making the problem tractable. Finally, an example is provided to illustrate the effectiveness and validation of the proposed method. [ABSTRACT FROM AUTHOR]

This paper considers the observer-based leader–follower consensus problem of multi-agent systems with one-sided Lipschitz conditions and quadratic inner-boundedness nonlinearity. Based on the relative outputs of neighboring agents, an adaptive protocol over a directed graph is designed via assigning a time-varying coupling weight to each node. Compared with the existing protocols, the proposed protocol can not only be utilized in the unidirectional flow of information, but it does not require any global graph information for its design. It has been shown that the established criteria can not only make the observer error tendency zero, but one can also achieve the leader–follower consensus of such nonlinear multi-agent systems. Furthermore, the gains of observer and protocol parameters can be constructed by solving the linear matrix inequalities (LMIs), which are conveniently checked. The results are illustrated by numerical simulations. [ABSTRACT FROM AUTHOR]

The study addresses the consensus problem of linear time invariant (LTI) multi‐agent systems with constant input delay and matched external disturbances by using relative output information. First, distributed disturbance observers are constructed to estimate the disturbances generated by linear exosystems with unknown initial conditions. Next, a disturbance observer‐based predictor feedback control law is developed for each agent to realise consensus disturbance rejection in the presence of input delay. Then, a linear matrix inequality‐based control design algorithm is given to determine the satisfactory control parameters. It is proved that state consensus can be achieved for both leaderless and leader–follower networks in the presence of large input delay and matched disturbances under the control scheme. Finally, a simulation example is provided to validate the theoretical results. [ABSTRACT FROM AUTHOR]

This paper addresses the robust consensus reliable control problem against actuator faults for linear parameter-varying multiagent systems. First, the actuator faults are modeled via a polytopic uncertainty method. Second, a distributed observer is designed for the single agent by sharing the communication network sensors to estimate the state information. Then by these estimated information, a robust consensus reliable control protocol against actuator faults is obtained and desired disturbance rejection performance can be guaranteed by this proposed protocol. Third, the nonconvexity conditions of the consensus control protocol can be translated into an linear matrix inequality optimization problem via simple matrix calculation. Finally, the effectiveness of the proposed reliable controller scheme is illustrated by two examples. [ABSTRACT FROM AUTHOR]

This paper addresses the T-S fuzzy modelling and H∞ attitude control in three channels for hypersonic gliding vehicles (HGVs). First, the control-oriented affine nonlinear model has been established which is transformed from the reentry dynamics. Then, based on Taylor’s expansion approach and the fuzzy linearization approach, the homogeneous T-S local modelling technique for HGVs is proposed. Given the approximation accuracy and controller design complexity, appropriate fuzzy premise variables and operating points of interest are selected to construct the T-S homogeneous submodels. With so-called fuzzy blending, the original plant is transformed into the overall T-S fuzzy model with disturbance. By utilizing Lyapunov functional approach, a state feedback fuzzy controller has been designed based on relaxed linear matrix inequality (LMI) conditions to stable the original plants with a prescribed H∞ performance of disturbance. Finally, numerical simulations are performed to demonstrate the effectiveness of the proposed H∞ T-S fuzzy controller for the original attitude dynamics; the superiority of the designed T-S fuzzy controller compared with other local controllers based on the constructed fuzzy model is shown as well. [ABSTRACT FROM AUTHOR]

Cooperative output regulation is a general framework, which considers output synchronisation, homogenisation and disturbance rejection simultaneously. To be an extension, this study divides the lumped disturbance into two parts, namely, local disturbance which is slow‐varying, mismatched and non‐linear, and global disturbance generated by an autonomous linear system. Generalised extended state observers (GESOs) are constructed to estimate the local states, the local disturbances and the global disturbance simultaneously. Observer‐based controllers are designed to realise cooperative output regulation in the presence of mismatched uncertainties. In control design, a linear matrix inequality‐based design methodology is proposed to get the exponentially convergent GESO with guaranteed decay rate. A simulation example is then shown to validate the theoretical results. [ABSTRACT FROM AUTHOR]

In this study, the authors mainly focus on the event‐triggered control design problem of networked control systems (NCSs) with dynamic quantisation and fault. The research contents are divided into two parts. The first part assumes that quantised measurements of the state are available, asymptotic stability analysis and feedback controller design of the event‐triggered NCSs with constant sensor fault and actuator fault are accomplished. The second part assumes that quantised measurements of the input are available, stochastic actuator fault, which is modelled by the Bernoulli distributed white sequence is considered in this situation, and a robust feedback controller is designed. At the end, numerical examples are given to illustrate the effectiveness of the obtained results. [ABSTRACT FROM AUTHOR]

This study addresses the finite‐frequency robust feedback controller design problem against actuator faults for linear parameter‐varying systems. First, a general model of actuator faults is presented. Then, sufficient conditions for the existence of the state‐feedback controller are obtained by using generalised Kalman–Yakubovich–Popov lemma and projection lemma, which guarantee that the closed‐loop system satisfies robustness performance in a finite‐frequency domain and is stable for both faults free and actuator faults. In addition, by introducing a state feedback gain, the non‐convexity conditions of the output‐feedback gain are derived. An iterative linear matrix inequality algorithm is proposed in this study to get the solution. The performances of the proposed reliable controller schemes are illustrated by two examples. [ABSTRACT FROM AUTHOR]

In this study, the authors investigate distributed model predictive control for polytopic uncertain systems subject to actuator saturations and packet dropouts with time‐varying probabilities in controller‐to‐actuator channels. For the sake of less computational efforts and a flexible system structure, the global system is decomposed into several lower‐dimensional subsystems and the subsystems optimise a global performance function in parallel. A novel augmented distributed controller model is proposed to describe both the actuator saturations and packet dropouts in one unified expression by adopting a stochastic variable taking the value 1 or 0 with time‐varying probabilities and accordingly a new result is obtained. By placing the saturated linear feedback law into the convex hull of a group of linear feedback laws, the distributed controller for each subsystem is obtained from the solution of the convex optimisation problem involving linear matrix inequalities. A numerical example is supplied to demonstrate the effectiveness of the developed techniques. [ABSTRACT FROM AUTHOR]