无人机编队保持反步容错控制

针对领导-跟随无人机编队中的执行器故障、不确定气动参数和外界扰动等问题，设计了无人机编队保持反步容错控制。建立了编队纵向、编队横向和编队高度三维误差模型，并将无人机本体方程分为快慢两个回路，建立包含外界扰动、不确定气动参数及执行器故障的无人机运动模型；设计内环容错控制系统，对编队外环控制器产生的指令信号进行跟踪。内环容错控制系统主要由3个部分组成：一是基于滑模观测器的故障检测和辨识，实现对故障执行器的定位和故障参数的辨识；二是将故障参数及干扰观测器与反步容错控制相结合，实现包容外界扰动、不确定气动参数和执行器故障的容错控制；三是内环容错控制系统稳定性分析。仿真结果表明，所提容错控制方法能够有效地实现无人机编队的飞行容错控制。

Back-stepping-fault-tolerant Control for Keeping the Formation of Unmanned Aerial Vehicles

A back-stepping-fault-tolerant control is proposed for keeping the formation of leader-follower unmanned aerial vehicles(UAV) under the conditions of actuator fault, uncertain aerodynamic parameters and external disturbance. The forward, lateral and altitude distance error models are described. An UAV motion model with actuator fault, external disturbance, and uncertain aerodynamic parameters is described. An inner loop fault-tolerant control system is designed to track the command signal produced by the outer loop formation controller. The inner loop fault-tolerant control system is consisted of three parts:one is the fault detection and identification (FDI) mechanism to locate the fault actuator and estimate the fault parameters; one combines back-stepping control with fault parameters and an adaptive disturbance observer to compensate for actuator faults, external disturbance, and uncertain aerodynamic parameters; the other one is the stability analysis of the inner loop controller system. The simulated results show that the proposed control method can be used for the fault-tolerant control of UAV formation.