This article investigates the prescribed-time fault-tolerant formation tracking problem in multiple unmanned helicopters subject to the both gain and bias actuator faults. In contrast to the existing results separating the underactuated model into outer-loop and inner-loop subsystems on the whole, three high-order fully actuated subsystems are derived for design convenience at first. Subsequently, a prescribed-time fault estimation observer is developed to approximate the subsystem states and lumped faults, which can be completed within a user-preassigned time regardless of the initial observation conditions. Such a convergence time can also determine the relevant parameters to some extent. Afterward, we incorporate the high-order fully actuated system approach into the prescribed-time fault-tolerant formation control protocol design procedures, to eliminate the influence of failures and preserve the target geometric pattern, in which an artificial repulsive potential function is utilized to avoid collisions among the followers on the xoy\mathbf {xoy}-plane. In this manner, the prescribed-time property and the higher tracking accuracy can be accomplished. Finally, simulation results are presented to prove the reliabilities and benefits of the algorithm.

中文翻译：

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无碰撞无人直升机的规定时间容错编队控制：一种高阶全驱动系统方法


本文研究了多架无人直升机在增益和偏置执行器故障的情况下的规定时间容错编队跟踪问题。与现有的将欠驱动模型整体分为外环和内环子系统的结果相反，为了设计方便，首先推导了三个高阶全驱动子系统。随后，开发了规定时间故障估计观测器来近似子系统状态和集中故障，无论初始观测条件如何，都可以在用户预先指定的时间内完成。这样的收敛时间也可以在一定程度上决定相关参数。随后，我们将高阶完全驱动系统方法纳入规定时间容错编队控制协议设计程序中，以消除故障的影响并保留目标几何图案，其中利用人工排斥势函数来避免xoy\mathbf {xoy} 平面上的追随者之间的碰撞。以这种方式，可以实现规定时间特性和更高的跟踪精度。最后给出了仿真结果，证明了算法的可靠性和优越性。