In this article, an event-triggered adaptive tracking control scheme is proposed for uncertain nonlinear systems with the predefined time-varying output constraint requirements by using barrier Lyapunov function (BLF) method. One of the significant novelties in the proposed design procedure is that the event-triggered control strategy is first designed jointly with nonlinear systems under the predefined time-varying output constraint requirements, such that the communication resources are effectively saved. Then, we set a time in advance to make the systems begin obeying the constraint requirements before running the time by using a shifting function nested in the first BLF. Meanwhile, the requirement (the initial value of the coordinate transformation needs to be in the constraints) is released by using the shifting function. For the unknown control gains in the considered system, a Nussbaum design procedure is employed to eliminate the effects of the unknown control gains. In addition, it is proved that all signals in the whole closed-loop system are bounded and the output constraint requirements are not violated. In the end, the simulation results illustrate the validity of the proposed scheme through a practical example.

中文翻译：

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基于 Nussbaum 设计的具有预定义时变输出约束的非线性系统的事件触发自适应跟踪控制

在本文中，针对具有预定义时变输出约束要求的不确定非线性系统，采用势垒李雅普诺夫函数（BLF）方法提出了一种事件触发的自适应跟踪控制方案。所提出的设计程序的重大创新之一是首先在预定义的时变输出约束要求下与非线性系统联合设计事件触发控制策略，从而有效地节省了通信资源。然后，我们通过使用嵌套在第一个 BLF 中的移位函数提前设置一个时间，使系统在运行时间之前开始遵守约束要求。同时，使用移位函数释放需求（坐标变换的初始值需要在约束中）。对于所考虑系统中的未知控制增益，采用 Nussbaum 设计程序来消除未知控制增益的影响。此外，证明了整个闭环系统中的所有信号都是有界的，并且没有违反输出约束要求。最后，仿真结果通过一个实例说明了所提出方案的有效性。