H∞ control for uncertain Takagi–Sugeno fuzzy systems with time-varying delays and nonlinear perturbations

This paper investigates the robust H_∞ control for Takagi–Sugeno (T–S) fuzzy systems with time-varying delays and nonlinear perturbations. Delay-dependent criteria for uncertain fuzzy systems have been proposed. The LMI optimization approach is applied to solve the H_∞ control problem and find the minimization of H_∞ norm bound. Computer simulations show that significant improvement over the previous results can be obtained.     

Resilient and robust finite-time H∞ control for uncertain discrete-time jump nonlinear systems

This paper studies the robust and resilient finite-time H_∞ control problem for uncertain discrete-time nonlinear systems with Markovian jump parameters. With the help of linear matrix inequalities and stochastic analysis techniques, the criteria concerning stochastic finite-time boundedness and stochastic H_∞ finite-time boundedness are initially established for the nonlinear stochastic model. We then turn to stochastic finite-time controller analysis and design to guarantee that the stochastic model is stochastically H_∞ finite-time bounded by employing matrix decomposition method. Applying resilient control schemes, the resilient and robust finite-time controllers are further designed to ensure stochastic H_∞ finite-time boundedness of the derived stochastic nonlinear systems. Moreover, the results concerning stochastic finite-time stability and stochastic finite-time boundedness are addressed. All derived criteria are expressed in terms of linear matrix inequalities, which can be solved by utilizing the available convex optimal method. Finally, the validity of obtained methods is illustrated by numerical examples.     

Robust stability of uncertain T–S fuzzy time-varying systems

In this paper, the global exponential stability for a class of uncertain Takagi–Sugeno (T–S) fuzzy time-varying systems is investigated. Based on the comparison theorem, a simple criterion is derived to guarantee the global exponential stability of such systems. An estimate of the exponential decay rate of such stable systems is also presented. Finally, a numerical example is provided to illustrate the use of the main result.     

Robust L ∞ reliable control for impulsive switched nonlinear systems with state delay

This paper investigates the problem of robust L _∞ reliable control for a class of uncertain impulsive switched nonlinear systems with time-delay in the presence of actuator failure. Based on the dwell time approach, we firstly obtain a sufficient condition of exponential stability for the impulsive switched nonlinear system with time-delay, and L _∞ performance for the considered system is also analyzed. Then, based on above results, a state feedback controller, which guarantees the exponential stability with L _∞ performance of the corresponding closed-loop system, is constructed. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed design method.     

Robust observer design for uncertain Itô neutral stochastic time-delay systems via sliding mode control

This paper deals with the output feedback sliding mode control for uncertain Itô neutral stochastic time-delay systems. The system states are unmeasured, and the uncertainties are unmatched. A sliding mode control scheme is proposed based on the state estimates. By utilizing a novel switching function, the derivative of the switching function is ensured to have a finite variation. It is shown that the sliding mode in the estimation space can be attained in finite time. A sufficient condition for the asymptotic stability (in probability) of the overall closed-loop stochastic system is derived. Finally, a simulation example is given to illustrate the proposed method.     

Type-2 T–S fuzzy impulsive control of nonlinear systems

A novel impulsive control approach based on interval Type-2 T–S fuzzy model has been presented for nonlinear systems in this paper. This approach makes up for the drawback of Type-1 fuzzy impulsive control, which cannot fully handle the uncertainties in describing the complex nonlinear systems by Type-1 fuzzy membership functions and cannot give rigorous fuzzy rules. Further more, this approach uses the “broad band” effect of the Type-2 membership functions to solve the noise of training data and exterior disturbance of the Type-1 fuzzy impulsive control. By using Lyapunov theory and Lipschitz condition, which is combined with integrated approaches such as comparison methods and linear matrix inequalities, the Type-2 fuzzy impulsive controller is designed and the general asymptotical stability analysis of the systems is given. Finally, the simulation of the inverted pendulum model demonstrates the validity and superiority of the proposed method by easily determining the membership functions and choosing minimum number of fuzzy rules and the method can handle random disturbance and data uncertainties very well.     

Improved stability and H∞ performance for neutral systems with uncertain Markovian jump

This paper addresses the problem of the delay-dependent stability and $H\infty$ performance for neutral systems with uncertain Markovian jump; the uncertainty of Markovian jump refers to the partial information on transition probability. In order to highlight the methods for the analysis of the systems, the neutral delay is assumed same as discrete delay. By the novel constructed Lyapunov functional, combining with the delay decomposition technique and free matrices, and using the new inequality rather than the Jensen inequality, the delay-dependent stability conditions are firstly obtained for the two kinds of neutral dynamical systems. Based on the stability condition, the $H\infty$ performance result for the systems with Markovian jump is secondly provided. All of the delay-dependent stabilization results are formulated in terms of LMIs, which can be easily checked by the LMI control toolbox in Matlab. Finally, two numerical examples are given to show the validity and potential of the developed criteria.