Purpose

The purpose of this study is to present a new integrated structure for a fault tolerant aircraft control system because fault diagnosis of flight control systems is extremely important in obtaining healthy flight. An approach to detect and isolate aircraft sensor faults is proposed, and a new integrated structure for a fault tolerant aircraft control system is presented.

Design/methodology/approach

As disturbance and sensor faults are mixed together in a flight control system, it is difficult to isolate any fault from the disturbance. This paper proposes a robust unknown input observer for state estimation and fault detection as well as isolation using fuzzy logic.

Findings

The dedicated observer scheme (DOS) and generalized observer scheme (GOS) are used for fault detection and isolation in an observer-based approach. Using the DOS, it has been shown through simulation that sensor fault detection and isolation can be made, but here the threshold value must be well chosen; if not, the faulty sensor cannot be correctly isolated. On the other hand, the GOS is more usable and flexible than the DOS and allows isolation of faults more correctly and for a fuzzy logic-based controller to be used to realize fault isolation completely.

Originality/value

The fuzzy logic approach applied to the flight control system adds an important key for sensor fault isolation because it reduces the effect of false alarms and allows the identification of different kinds of sensor faults. The proposed approach can be used for similar systems.

中文翻译：

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基于未知输入观测器的容错飞行控制系统模糊鲁棒故障估计方案

目的

本研究的目的是为容错飞机控制系统提供一种新的集成结构，因为飞行控制系统的故障诊断对于获得健康飞行极为重要。提出了一种检测和隔离飞机传感器故障的方法，并提出了一种新的容错飞机控制系统的集成结构。

设计/方法/方法

由于干扰和传感器故障在飞行控制系统中混合在一起，因此很难将任何故障与干扰隔离开来。本文提出了一种鲁棒的未知输入观察器，用于状态估计和故障检测以及使用模糊逻辑的隔离。

发现

专用观察器方案 (DOS) 和广义观察器方案 (GOS) 用于在基于观察器的方法中进行故障检测和隔离。使用DOS，通过仿真表明可以进行传感器故障检测和隔离，但这里的阈值必须选择好；如果不是，则无法正确隔离故障传感器。另一方面，GOS 比 DOS 更易用和灵活，可以更正确地隔离故障，并且可以使用基于模糊逻辑的控制器来完全实现故障隔离。

原创性/价值

应用于飞行控制系统的模糊逻辑方法为传感器故障隔离增加了一个重要的关键，因为它减少了误报的影响，并允许识别不同类型的传感器故障。所提出的方法可用于类似的系统。