This paper investigates the fixed-time cooperative output regulation (FTCOR) problem with unknown exosystem of second-order nonlinear multiagent systems. To solve this problem, it is necessary to ensure that each agent can obtain the reference trajectory originating from an unknown exosystem and reconstruct the solution of the regulator equation containing the exogenous signal and unknown parameter vectors within a fixed time, and the unknown exosystem makes it difficult to solve these two problems with existing tools. By using auxiliary filtering variables, we propose a fixed-time adaptive distributed observer (FTADO) and design a fixed-time distributed internal model (FTDIM) based on this FTADO. These two new tools ensure the solvability of the two problems just mentioned. Then, based on these two tools, we transform the problem into a fixed-time stabilization problem of a so-called augmented system. Through the backstepping technique, we propose a distributed controller that solves this fixed-time stabilization problem while relaxing the assumptions of similar references.

中文翻译：

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外系统未知的二阶非线性多智能体系统的固定时间协同输出调节


本文研究了二阶非线性多智能体系统未知外系统的固定时间协同输出调节（FTCOR）问题。为了解决这个问题，需要保证每个智能体都能获得源自未知外系统的参考轨迹，并在固定时间内重构包含外源信号和未知参数向量的调节方程的解，而未知外系统使得现有工具很难解决这两个问题。通过使用辅助滤波变量，我们提出了固定时间自适应分布式观测器（FTADO），并基于该FTADO设计了固定时间分布式内部模型（FTDIM）。这两个新工具确保了刚才提到的两个问题的可解决性。然后，基于这两个工具，我们将问题转化为所谓增强系统的固定时间稳定问题。通过反步技术，我们提出了一种分布式控制器，可以解决这个固定时间稳定问题，同时放宽类似参考文献的假设。