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This article is devoted to the event‐triggered practical tracking control for a class of high‐order nonlinear systems with serious uncertainties. Remarkably, the serious uncertainties are greatly reflected from the unknown control directions and input powers which give rise to essential obstacles in control design and hence lead to incapability of the traditional control methods on this topic. To solve the control problem, a novel switching event‐triggered control scheme is proposed by a skillful incorporation of logic‐based switching mechanism into the event‐triggered one. Specifically, two pivotal events are smartly chosen to give the event‐triggered mechanism for the determination of the sampling times. In particular, one of the events is used to give the switching varying mechanism, by which the controller parameters are respectively switched in two groups of sequences which are carefully chosen for the compensation of serious uncertainties. Under the proposed switching event‐triggered mechanism, a state‐feedback controller is designed which guarantees that all the signals of the closed‐loop system are bounded while system output practically tracks the reference signal, along with a finite number of switching of controller parameters as well as the exclusion of the Zeno phenomenon. Finally, simulation examples are provided to validate the effectiveness of the proposed theoretical results. [ABSTRACT FROM AUTHOR]

This paper comprehensively explores the stability analysis of random nonlinear systems subjected to random non‐instantaneous multiple impulses. The random non‐instantaneous multiple impulses refer to various impulsive intensities, with the type of impulse at each moment determined by a Markov chain. Drawing on the properties of stochastic processes, a series of stability criteria are developed for the random non‐instantaneous multiple impulsive systems within the constraint of fixed impulsive intervals. To validate the practicality of the proposed conceptual methods, the tracking control problem of network surface vessels under deception attacks is investigated, demonstrating feasibility through simulation results. [ABSTRACT FROM AUTHOR]

This paper is devoted to the event-triggered consensus control for a class of uncertain multiple Euler-Lagrange (EL) systems with actuator faults. Different from the related works where strict conditions are imposed on system uncertainties and the measurements of the leader's output, more serious uncertainties are involved since all the system dynamic matrices are unknown while both actuator faults and external disturbance are considered; and moreover, fewer measurements of the leader's output are required since its time derivatives are not necessarily available for feedback. Mainly because of these, the consensus problem is hard to solve by straightforwardly extending the existing results. To solve the control problem, a dynamic gain with a smart choice of its updating law is introduced to overcome the serious uncertainties and the sampling error of the control signal. By incorporating the dynamic gain into the vectorial backstepping procedure, an adaptive consensus controller joined with an event-triggered mechanism is designed for each follower to ensure the consensus of the multi-agent system in the sense that all the states of the closed-loop system are bounded while the output of each follower tracks the leader's output. Finally, the effectiveness of the proposed method is verified by a simulation example. [ABSTRACT FROM AUTHOR]

This article investigates practical tracking joint with obstacle‐avoidance for a class of uncertain robotic systems. The remarkable features are revealed from two aspects. First, more serious system uncertainties are allowed than the related literature due to the presence of unknown system matrices and mismatched disturbance in the investigated system. Second, only coarse conditions are required on reference trajectory and obstacles since their time derivatives are not necessarily to be available for feedback but those of the related literature muse be, while the reference trajectory is only required to be first rather than second order continuously differentiable. For this, a secure adaptive control framework is established by incorporating adaptive dynamic compensation mechanism into the backstepping procedure with the smart choice of adaptive law and the skillful injection of a barrier function. Consequently, a state‐feedback controller is explicitly designed which guarantees the obstacle‐avoidance of the robotic system while all the signals of the resulting closed‐loop system are bounded with system output practically tracking the reference trajectory. Finally, simulation results are provided for two specified robot systems to validate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]