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This article discusses the finite‐time boundedness (FTB) issue and L2$$ {L}_2 $$‐gain analysis for switched stochastic systems, particularly under the dual influence of DoS attacks and false data injection attacks, by employing a novel event‐triggered mechanism. Different from the moment calculation method, a probability‐based FTB is studied which offers more pertinence. To obtain a less conservative condition of FTB, a switched Lyapunov function is constructed. Additionally, a memory‐based dynamic event‐triggered mechanism is designed to reduce the amounts of triggering and mitigate the state response fluctuations. Based on the incomplete information above, state feedback controllers are devised to satisfy stochastic FTB, ensuring the successful attainment of finite‐time L2$$ {L}_2 $$‐gain. Sufficient conditions are cast into a convex optimization problem by LMIs which can be solved easily. Finally, a compared numerical example and an RLC series circuit are adopted to demonstrate the availability of the theoretical results. [ABSTRACT FROM AUTHOR]

Finite‐time non‐smooth stabilization of cascade output‐constrained switched systems via state feedback is investigated. The cascade switched systems consist of subsystems in general form with zero dynamics and mixed powers taken into account. To deal with the finite‐time stabilization problem of such kind of switched systems, some mild assumptions, input‐to‐state stability property of zero dynamics, an appropriate growth rate assumption on nonlinear terms and some well‐known conditions for small signals, have been imposed on subsystems. Then, state feedback controllers are constructed first by revamping adding a power integrator technique and finite‐time stability analysis of the resultant closed‐loop switched systems are implemented by the deliberately constructed tangent‐type barrier Lyapunov function (Tan$$ {T}_{an} $$‐BLF). Meanwhile, the output constraint of switched systems is also implicitly guaranteed by the Tan$$ {T}_{an} $$‐BLF. Switched systems discussed in this article can encompass almost all p$$ p $$‐normal ones because of the inclusion of zero dynamics, mixed powers, and the homogenous upper bounded assumption on nonlinear terms. And, the method proposed in this article operates in a unified framework to tackle finite‐time stabilization of switched systems because the constructed common Tan$$ {T}_{an} $$‐BLF degenerates into a quadratic function when the output constraint tends to infinity. Simulations are carried out to show the efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

Summary: In the framework of sampled‐data control, finite‐time boundedness (FTB) of switched systems with time‐varying delays is investigated. Sufficient conditions for FTB of switched systems with time‐varying delays via sampled‐data control are proposed. Moreover, considering the relationship between the sampling period and the mode‐dependent average dwell time, switching signals are designed. In addition, finite‐time weighted L2‐gain (FTW‐L2‐gain) of switched systems with time‐varying delays is proposed to measure their disturbance tolerance capacity within a finite‐time interval. Multiple Lyapunov‐Krasovskii functionals are applied to complete subsequent proofs in detail. Simulation results are exemplified to verify the proposed method. [ABSTRACT FROM AUTHOR]

Summary: In this article, we investigate the formation control problem of multiquadrotor aircraft system subject to connectivity preservation and collision avoidance. First, based on the backstepping design method, a novel formation control algorithm is developed to enable multiquadrotor aircraft to move along the desired trajectory while becoming the predefined formation pattern. Meanwhile, the connectivity of the communication network is maintained and the collision among multiquadrotor is avoided. Second, for each quadrotor's desired attitude obtained by the formation controller, an improved finite‐time attitude tracking law is designed to guarantee that the desired attitude can be tracked by the real attitude in a fast finite time. Finally, a numerical example is given to demonstrate the effectiveness of the proposed algorithms. [ABSTRACT FROM AUTHOR]

ABSTRACT In this paper, the adaptive non‐smooth fixed‐time state feedback stabilization problem of output‐constrained switched systems are investigated. In order to well deal with the output constrains and uncertain parameters, a common barrier Lyapunov function which includes a tangent‐type term of the system state and a quadratic term of the uncertain parameter estimation error is constructed. Adaptive fixed‐time state feedback controllers and parameter update laws are designed by virtue of adding a power integrator technique with some mild assumption imposed on the subsystem's nonlinear terms. Simulation results of a numerical example and a two‐tank liquid‐level system presented in this paper explicitly demonstrate the effectiveness of the proposed approach in this paper. Subsystems powers considered in this article only need to be greater than zero, regardless of odd or even numbers, which make the structure of switched systems more general. The proposed method provides us to perform the design of the adaptive fixed‐time stabilizers for switched systems with/without output constraints simultaneously with the same controller structure, which means it has a unified nature. [ABSTRACT FROM AUTHOR]

Summary: In this paper, globally asymptotical stabilization problem for a class of planar switched nonlinear systems with an output constraint via smooth output feedback is investigated. To prevent output constraint violation, a common tangent‐type barrier Lyapunov function (tan‐BLF) is developed. Adding a power integrator approach (APIA) is revamped to systematically design state‐feedback stabilizing control laws incorporating the common tan‐BLF. Then, based on the designed state‐feedback controllers and a constructed common nonlinear observer, smooth output‐feedback controllers, which can make the system output meet the predefined constraint during operation, are proposed to deal with the globally asymptotical stabilization problem of planar switched nonlinear systems under arbitrary switchings. A numerical example is employed to verify the proposed method. [ABSTRACT FROM AUTHOR]

This paper investigates the global asymptotic stabilization problem for a class of nonlinear systems with time-varying powers. First, adding a power integrator technique is revamped to design a smooth state feedback controller, which is implementable with only upper and lower bounds of the time-varying powers. When the system state is not fully available and the time-varying power is exactly known, a smooth output feedback controller constituted by a state feedback and a nonlinear state observer is constructed to globally stabilize the system. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY Finite-time formation control of multiple second-order agents via dynamic output feedback is investigated in this paper. Under the assumption that the velocities of all agents cannot be measured, a continuous consensus algorithm is first proposed such that the states of all agents will reach an agreement in finite time. Then, the consensus algorithm is applied to the finite-time formation control, including stationary formation and moving formation, respectively. Rigorous proof shows that all agents will converge to the desired formation pattern in finite time. Finally, an example is given to verify the efficiency of the proposed method. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]