Dynamic Output Feedback Control for Systems Subject to Actuator Saturation via Event‐Triggered Scheme

OUTPUT FEEDBACK STOCHASTIC STABILIZATION OF ACTIVE FAULT TOLERANT CONTROL SYSTEMS: LMI FORMULATION

In this paper, a new stabilization condition of switched fuzzy systems is proposed. The dynamic output feedback control problem is addressed for a class of switched fuzzy Systems. The dynamic output feedback with sufficient conditions and the design method of controller is given using multiple Lyapunov function method and switching law. The closed-loop system asymptotically stable is given by the designed controller. Adopting the dynamic output feedback control law, the order of the closed-loop system is reduced, which is helpful to improve the reliability of the system. Finally, simulation results verify the effectiveness of the conclusion.

The H∞ dynamic output feedback control problem for a class of discrete‐time switched time‐delay systems under asynchronous switching is investigated in this paper. Sensor nonlinearity and missing measurements are considered when collecting output knowledge of the system. Firstly, when there exists asynchronous switching between the switching modes and the candidate controllers, new results on the regional stability and l2 gain analysis for the underlying system are given by allowing the Lyapunov‐like function (LLF) to increase with a random probability. Then, a mean square stabilizing output feedback controller and a switching law subject to average dwell time (ADT) are obtained with a given disturbance attenuation level. Moreover, the mean square domain of attraction could be estimated by a convex combination of a set of ellipsoids, the number of which depends on the number of switching modes. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.

This paper considers the design problem of dynamic output feedback control for fractional-order (FO) Takagi-Sugeno fuzzy systems with uncertain parameters. Via the application of FO system stability theory, robust control method and the linear matrix inequality techniques, sufficient conditions are given for the stability analysis and the existence of the dynamic fuzzy output feedback controllers. The dynamic output feedback controller designed here guarantees the robust stability of the closed-loop system. Finally, a fractional order chaotic system simulation example is given to illustrate the effectiveness of the design approach here.

This article deals with the codesign of an output-dependent switching function and a full-order affine filter for discrete-time switched affine systems. More specifically, from the measured output, the switched filter has the role of providing essential information for the switching function, which must assure global practical stability of a desired equilibrium point. The design conditions are based on a general quadratic Lyapunov function and are expressed in terms of linear matrix inequalities. Moreover, whenever the system is quadratically detectable, the solution to the output feedback problem coincides with the one for the state feedback case and the associated filter admits the observer form. To the best of the authors' knowledge, this is the first time that the dynamic output feedback control problem is treated in the context of discrete-time switched affine systems. The results can be used to cope with sampled-data control and have the property of assuring global asymptotic stability when the sampling period tends to zero. A practical application concerning the velocity control of a dc motor driven by a buck-boost converter illustrates the theoretical results.

In this paper, dynamic output feedback control problem is investigated for a class of nonlinear interconnected systems with time delays. Decentralized observer independent of the time delays is first designed. Then, we employ the bounds information of uncertain interconnections to construct the decentralized output feedback controller via backstepping design method. Based on Lyapunov stability theory, we show that the designed controller can render the closed-loop system asymptotically stable with the help of the changing supplying function idea. Furthermore, the corresponding decentralized control problem is considered under the case that the bounds of uncertain interconnections are not precisely known. By employing the neural network approximation theory, we construct the neural network output feedback controller with corresponding adaptive law. The resulting closed-loop system is stable in the sense of semiglobal boundedness. The observers and controllers constructed in this paper are independent of the time delays. Finally, simulations are done to verify the effectiveness of the theoretic results obtained.

This paper investigates the dynamic output-feedback control problem for active suspension systems subject to actuator faults in finite frequency domain. Unmeasured states and uncertain parameters are considered in the controller design process. By using the generalized Kalman-Yakubovich-Popov (KYP) lemma, an H ∞ controller can be obtained in specific frequency band. The H ∞ controller is used to make passengers ride comfort under road disturbance. Moreover, the constraints of active suspension systems can be guaranteed depended on the designed controller. Finally, simulations are presented to illustrate the effectiveness of the proposed controller.

This paper concerns the robust passive control problem for linear systems with norm-bounded time-varying uncertainties in all the system matrices. Our objective is to design a feedback controller such that the closed-loop system is both quadratically stable and strictly passive for all admissible uncertainties. It is shown that such a problem is equivalent to a scaled strictly positive real control problem for a certain linear time-invariant system in which no uncertainty occurs. Therefore, a complete solution can be obtained by using the existing results of standard positive real control.

Dynamic output-feedback control for nonlinear continuous-time systems based on parametric uncertain subsystem and interval type-2 fuzzy model

The problem of dynamic output-feedback control for nonlinear time-delay systems is studied whose nonlinearities satisfy the homogeneous growth condition. Compared with the existing work, the growth rate here is an unknown constant. We introduce two adaptive gains to handle the unknown growth rate. A homogeneous output-feedback controller is explicitly developed by adding one power integrator method. It is proved that all the signals of the closed-loop system are bounded, meanwhile the system state globally converges to the origin. Finally, we used the proposed method to a two-stage chemical reactor as an application example.

This paper investigates the H ∞ control problem for linear system over networks with random communication data dropout and actuator saturation. The random data dropout process is modeled by a Bernoulli random binary distribution and the input saturation is confined in a convex hull by introducing a group of auxiliary matrices. By constructing a quadratic Lyapunov function, effective conditions for the state feedback-based H ∞ controller are proposed in the form of non-convex matrix inequalities to take the random data dropout and actuator saturation into consideration simultaneously, and the problem of non-convex feasibility is solved by applying cone complementarity linearization (CCL) procedure. Finally, a simulation example is given to demonstrate the effectiveness of the proposed new design techniques.

This paper investigates the problem of event-triggered dynamic output feedback control for networked Takagi-Sugeno (T-S) fuzzy systems with asynchronous premise variables. Our attention is focused on the design of an event-triggered fuzzy dynamic output feedback controller that guarantees that the closed-loop system is asymptotically stable. First, with consideration of the limited bandwidth and restricted network resource, an event-triggered communication scheme is proposed to save the limited network resource. Second, different from the existing results in the literature, a fuzzy dynamic output feedback controller with asynchronous premise variables is constructed such that the premise membership functions are not necessarily the same as the networked T-S fuzzy systems. Then, by using the Wirtinger inequality and some slack matrices, a less conservative stability and stabilization conditions for the existence of fuzzy dynamic output feedback controller are derived in the form of linear matrix inequalities, which can be solved by the standard MATLAB toolbox. Finally, an example is given to demonstrate the effectiveness of the designed event-triggered fuzzy dynamic output feedback controller.

This paper considers linear systems subject to sensor and actuator saturations, for which a dynamic output feedback controller has been a priori designed. The effects of unmodeled dynamics appearing as additive uncertainties are studied with respect to the regional (local) stability of the closed-loop system. Constructive conditions based on matrix inequalities, or at least linear matrix inequalities (LMI) are proposed in order to minimize the influence of these unmodeled dynamics on both the estimate of the closed-loop system basin of attraction and on the performance.

In this paper, the $\boldsymbol{L}_{\infty}$ control synthesis problem for linear systems subject to actuator saturation and persistent bounded disturbance is studied. An $\boldsymbol{L}_{\infty}$ dynamic output feedback controller, an anti-windup compensator and an event generator are simultaneously designed. First, by using the quadratic Lyapunov function technique, a sufficient condition on the existence of the $\boldsymbol{L}_{\infty}$ dynamic output feedback controller, an anti-windup compensator and an event generator is established via linear matrix inequalities (LMIs). Such an integrated controller is able to guarantee the regional stabilization and the $\boldsymbol{L}_{\infty}$ performance of linear systems with actuator saturation and external persistent bounded disturbance. Second, novel algorithms are developed to optimize the upper bound on the $\boldsymbol{L}_{\infty}$ performance, the event-triggered threshold and the domain of attraction. Moreover, an output-based event-triggered mechanism applying to the anti-windup dynamic output feedback control design is provided, which reduces the number of control actuation updates and information transmission with respect to the traditional time-triggered control scheme.

Dynamic output feedback controller design for affine T–S fuzzy systems with quantized measurements