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In this paper, the issue of output feedback finite‐time stabilization is investigated for a class of p‐norm stochastic systems with output constraints. A novel tan‐type barrier Lyapunov function (BLF) is constructed to cope with the constraint on the system output, and a finite‐time state feedback controller is subsequently designed by the adding a power integrator technique. Then, based on the designed state feedback controller and a devised nonsmooth observer for the unmeasurable state, the output feedback finite‐time stabilizer is obtained. Both the theoretical analysis and numerical example demonstrate that the proposed scheme guarantees the finite‐time stability of the considered system without violating the prespecified output constraint. [ABSTRACT FROM AUTHOR]

Summary: This paper presents sufficient conditions to ensure the exponential stability of uncertain switched time‐delay systems with time‐delayed state‐dependent switching conditions, which can model high speed supercavitation vehicles (HSSVs). Based on the intrinsic properties of HSSVs, cavity can be represented by a relation between the states and time‐delayed states of the system. Moreover, a sliding behavior can be occurred at the cavity boundary in HSSVs. Therefore, the main contribution of this paper is to develop a set of LMI stability conditions in the presence of time‐delayed states in the linear state‐dependent switching signal and absorbing sliding modes in the state space, simultaneously. In addition, because of the possible existing uncertainties in HSSVs, another set of LMI‐based sufficient conditions is derived in order to analyze the stability of switched time‐delay systems with additive norm bounded uncertainties. The application of the proposed theorems are also validated through numerical examples. Finally, the stability of a two‐degrees‐of‐freedom longitudinal description of an HSSV is shown using the proposed stability theorems. [ABSTRACT FROM AUTHOR]

This paper presents feedback sensitivity functions analysis of implicit Lyapunov function-based control system in case of finite-time stabilization problem. The Gang of Four is chosen as a feedback sensitivity tool. The results can be used for parametric tuning of control algorithms in order to guarantee desired closed-loop sensitivity specifications. The obtained results are supported by numerical examples. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: This paper investigates the pth moment exponential input‐to‐state stability (ISS) of nonlinear discrete‐time impulsive stochastic delay systems. By employing Lyapunov functionals, some pth moment exponential ISS criteria are provided. The obtained results show that a discrete‐time stochastic delay system can become pth moment exponential input‐to‐state stable by impulsive controls even if it may be not input‐to‐state stable itself. On the other hand, the original system without impulses can retain its ISS property with appropriate destabilizing impulses. As an application, the theoretical results are used to test the ISS for a class of recurrent neural networks under stochastic perturbations. Finally, a numerical example is presented to illustrate the effectiveness of the results. [ABSTRACT FROM AUTHOR]

Summary: This paper investigates the problem of gain‐scheduled output feedback control design for continuous‐time linear parameter varying systems. The scheduling parameters are supposed to be measured in real time with absolute uncertainties and proportional uncertainties, simultaneously. Using a nonlinear transformation, the problem is formulated in terms of solutions to a set of parameter‐dependent linear matrix inequalities, exploiting parameter searches for two scalar values. H∞‐type problem is treated using parameter‐dependent Lyapunov and auxiliary matrices. One of the advantages of the presented method lies in its less conservatism in comparison with the available approaches. Some numerical examples are given to illustrate the effectiveness and advantage of the proposed method. [ABSTRACT FROM AUTHOR]

Summary: In this paper, collaborative distributed dynamic output‐feedback control problem is investigated for a class of wireless control systems with Markovian‐type control network and distributed network‐induced delays. The network consists of a set of interconnected nodes characterized by a directed graph with an adjacency matrix that specifies space distribution (ie, interconnection topology). Each node of wireless control systems not only routes information but also performs its local control. We assume measurements and distributed network‐induced delays are subject to two independent Markovian chains. It is shown that the collaborative distributed dynamic output‐feedback approach offers better performances compared with noncollaborative distributed control approach. An irrigation canal system is used to demonstrate practical potentials of the developed control strategy. [ABSTRACT FROM AUTHOR]

Summary: This paper investigates the distributed tracking control of a group of underactuated quadrotors in the presence of actuator faults in three‐dimensional space. Using consensus protocol and sliding mode algorithm, a distributed finite‐time fault‐tolerant formation control scheme is developed. The whole closed‐loop system is composed by position loop, attitude loop, and propeller speed loop. A propeller speed fault‐tolerant controller is developed to deal with the unexpected faults of quadrotors. The finite‐time stability of the closed‐loop system is guaranteed through Lyapunov analysis. Finally, the efficiency of the proposed algorithm is illustrated by some numerical simulations. [ABSTRACT FROM AUTHOR]

Summary: In this paper, we present the vibration control design for a string with the boundary time‐varying output constraint. The dynamics of the string is a distributed parameter system described by a partial differential equation and two ordinary differential equations. A barrier Lyapunov function with a logarithmic function is adopted to prevent the time‐varying constraint violations. Adaptive control is designed to handle the system parametric uncertainties. Stability analysis and the solvability of the inequality equations are provided. Numerical simulations are provided to illustrate the effectiveness of the proposed control design. [ABSTRACT FROM AUTHOR]

Summary: Domain of attraction plays an important role in stability analysis and safety verification of nonlinear control systems. In this paper, based on the concept of multiple Lyapunov‐like functions, we propose iteration algorithms for computing inner estimates of domains of attraction for a class of switched hybrid systems, where the state space is composed of several regions and each region is described by polyhedral sets. Starting with an initial inner estimate of domain of attraction, we firstly present a theoretical framework for obtaining a larger inner estimate by iteratively computing multiple Lyapunov‐like functions. Successively, the theoretical framework is underapproximatively realized by using S‐procedure and sums of squares programming, associated with the coordinatewise iteration method. Afterwards, for obtaining a required initial inner estimate of domain of attraction, we propose an alternative higher‐order truncation and linear semidefinite programming based method for computing a common Lyapunov function. Especially, a bisection method based improvement is proposed for obtaining better estimates in each iteration step. Finally, we implement proposed algorithms and test them on numerical examples with comparisons. These computation and comparison results show that the advantages of our multiple Lyapunov‐like functions based algorithm. Especially, we provide alternative underapproximations for avoiding the possible numerical problem. [ABSTRACT FROM AUTHOR]

Semi-Markovian jump systems, due to the relaxed conditions on the stochastic process, and its transition rates are time varying, can be used to describe a larger class of dynamical systems than conventional full Markovian jump systems. In this paper, the problem of stochastic stability for a class of semi-Markovian systems with mode-dependent time-variant delays is investigated. By Lyapunov function approach, together with a piecewise analysis method, a sufficient condition is proposed to guarantee the stochastic stability of the underlying systems. As more time-delay information is used, our results are much less conservative than some existing ones in literature. Finally, two examples are given to show the effectiveness and advantages of the proposed techniques. [ABSTRACT FROM AUTHOR]

This paper focuses on the robust output precise tracking control problem of uncertain nonlinear systems in pure-feedback form with unknown input dead zone. By designing an extended state observer, the states unmeasurable problem in traditional feedback control is solved, and the lumped uncertainty, which is caused by system unknown functions and input dead zone, is estimated. In order to apply separation principle, finite-time extended state observer is designed to obtain system states and estimate the lumped uncertainty. Then, by introducing tracking differentiator, a modified dynamic surface control approach is developed to eliminate the 'explosion of complexity' problem and guarantee the tracking performance of system output. Because tracking differentiator is a fast precise signal filter, the closed-loop control performance is significantly improved when it is used in dynamic surface control instead of first-order filters. The L ∞ stability of the whole closed-loop system, which guarantees both the transient and steady-state performance, is shown by the Lyapunov method and initialization technique. Numerical and experiment examples are performed to illustrate our proposed control scheme with satisfactory results. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: The problem of impulsive stabilization of linear neutral delay systems is investigated by using the impulse‐time‐dependent Lyapunov functions. The construction of impulse‐time‐dependent Lyapunov functions is based on the singular system representation of the impulsively controlled neutral delay system. In order to overcome the difficulty arising from time‐varying state delays, a Razumikhin‐type analysis method is developed and the key technique is to establish the relation between the slow and fast state variables by using a difference inequality. The derived stability criterion weakens the restriction condition on the impulse operators found in the previous result. For constant delay case, an improved stability criterion is derived by applying an impulse‐time‐dependent Lyapunov functional. Next, based on the newly established stability criteria, novel sufficient conditions on the existence of impulsive controllers with range dwell‐time constraint are presented. Finally, two numerical examples are given to demonstrate the effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]