This work focuses on the issue of event-triggered practical prescribed time tracking control for a type of uncertain nonlinear systems subject to actuator saturation and unmeasurable states as well as time-varying unknown control coefficients. First, a state observer with simple structure is constructed by means of neural network technology to estimate the unmeasurable system states under time-varying control coefficients. Then, with the help of one-to-one nonlinear mapping of the tracking error, an event-triggered output feedback control scheme is developed to steer the tracking error into a residual set of predefined accuracy within a preassigned settling time. Unlike existing related control methods, there is no need to involve finite-time state observer or fractional power feedback of system states, and thus, the control solution presented here is less complex and more acceptable. The key technique in control design lies in the establishment of an alternative first-order auxiliary system for dealing with the impact arisen from the input saturation. In our proposed approach, a new bounded function related to auxiliary variable and new dynamics of the auxiliary system are skillfully utilized such that the upper bound of the difference between actual input and designed input signal is not involved in implementation of the controller.
In this paper, the sampled-data-based event-triggered tracking control for the positive nonlinear system is discussed. The event-triggered mechanism naturally causes a mismatch between the membership functions of the system model and the fuzzy controller. Meanwhile, the positive constraint and tracking behavior increase the complexity of system analysis and bring conservative analysis results.
This paper investigates the unified tracking control problem for a class of high-order nonlinear systems with 7 kinds of irregular state constraints and input saturation based on the dynamic event-triggered mechanism. The irregular state constraints exist in practical systems, including time-varying constraints, alternation between positive and negative bounds, adding/removing constraints during system operation, and the state of the system being constrained only by the upper/lower boundaries. Auxiliary constraint boundaries are introduced to deal with these irregular state constraints.
This paper explores the dynamic characteristics and a novel event-triggered practical prescribed-time controller for four complex coupled Duffing-type MEMS resonators. Initially, the effects of mechanical coupling stiffness, electrostatic coupling stiffness, and internal system parameters on the system's dynamic behavior are examined. The analysis results provide guidance for selecting system parameters.
The leader-following consensus issue for general linear multiagent systems (MASs) is investigated under event-triggered communication (ETC). Based on the output measurement of agent, two novel adaptive dynamic event-triggered (ADET) strategies for synchronous and asynchronous ETC are proposed, in which adaptive triggering parameters and time-varying threshold are introduced. Simultaneously, the corresponding control protocols are developed under the ADET strategies.
This paper studies input-to-state stabilization of delayed discrete-time Takagi-Sugeno (T-S) fuzzy systems via aperiodically intermittent control. We first consider aperiodically intermittent time-triggered control, where we present sufficient conditions via the mathematical induction under the hypotheses of the quasiperiodicity condition. Based on the derived sufficient conditions, we apply a Lyapunov-Krasovskii (L-K) method together with the descriptor method to derive the explicit linear matrix inequalities (LMIs) that ensure the exponential stability and input-to-state stability (ISS), and show the existence of the aperiodically intermittent time-triggered controller that leads to efficient results with much less numerical complexity.
