In this paper, the typical fault estimation and dynamic analysis are presented for a leader-follower unmanned aerial vehicle (UAV) formation system with external disturbances. Firstly, a dynamic model with proportional navigation guidance (PNG) control of the UAV formation is built. Then, an intermediate observer design method is adopted to estimate the system states and faults simultaneously. Based on the graph theory, the topology relationship between each node in the UAV formation has been also analyzed. The estimator and the system error have been created. Moreover, the typical faults, including the components failure, airframe damage, communication failure, formation collision, and environmental impact, are also discussed for the UAV system. Based on the fault-tolerant strategy, five familiar fault models are proposed from the perspectives of fault estimation, dynamical disturbances, and formation cooperative control. With an analysis of the results of states and faults estimation, the actuator faults can be estimated precisely with component failure and wind disturbances. Furthermore, the basic dynamic characteristics of the UAV formation are discussed. Besides, a comparison of two cases related to the wind disturbance has been accomplished to verify the performance of the fault estimator and controller. The results illustrate the credibility and applicability of the fault estimation and dynamic control strategies for the UAV system which are proposed in this paper. Finally, an extension about the UAV formation prognostic health management system is expounded from the point of view of the fault-tolerant control, dynamic modeling, and multifault estimation.

中文翻译：

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跟随式无人飞行器编队的典型故障估计和动力学分析

本文针对具有外部干扰的领导跟随者无人机编队系统，提出了典型的故障估计和动力学分析方法。首先，建立了具有比例导航制导（PNG）控制的无人机编队动力学模型。然后，采用中间观测器设计方法来同时估计系统状态和故障。基于图论，还分析了无人机编队各节点之间的拓扑关系。估算器和系统错误已创建。此外，还讨论了无人机系统的典型故障，包括组件故障，机身损坏，通信故障，编队碰撞和环境影响。根据容错策略，从故障估计，动力扰动和地层协调控制的角度提出了五个常见的故障模型。通过对状态和故障估计结果的分析，可以精确估计执行器故障，其中包括组件故障和风干扰。此外，还讨论了无人机编队的基本动力特性。此外，还完成了两种与风扰有关的案例的比较，以验证故障估计器和控制器的性能。结果证明了本文提出的无人机系统故障估计和动态控制策略的可靠性和适用性。最后，从容错控制的角度对无人机编队预后健康管理系统进行了扩展，