Flexible spacecraft active fault tolerant control method based on dynamic output feedback control

Abstract

The invention discloses a flexible spacecraft active fault tolerant control method based on dynamic output feedback control, which belongs to the field of spacecraft attitude control. The method comprises the steps that a dynamic equation of a flexible spacecraft attitude control system is transformed into a general state space equation; a fault model with additive sensor measurement offset is established; a fault detection and identification module composed of an unknown input observer and a filter is established; real-time detection and on-line estimation are carried out on unknown sensor fault; and a fault tolerant controller based on dynamic output feedback is designed based on acquired fault estimation information. According to the invention, when a flexible spacecraft can normally reach an expected posture in the case of an additive sensor measurement offset fault; the influence of disturbance generated by modeling uncertainty and flexible accessory is considered in a design process; and a fault diagnosis and identification module and the fault tolerant controller can be independently designed, and can be easily realized by a project.

Description

technical field [0001] The invention belongs to the field of aerospace flight control, in particular to a method for fault diagnosis and fault-tolerant control of a flexible spacecraft. Background technique [0002] Stable spacecraft attitude control is one of the necessary conditions to ensure the normal operation of the spacecraft. Flexible spacecraft generally carry a variety of complex flexible accessories that can perform a variety of tasks in orbit. Therefore, there are the following challenges for the attitude control system of flexible spacecraft: On the one hand, the complex dynamic characteristics of flexible Modeling increases uncertainty and will cause disturbances to the attitude of the spacecraft body; on the other hand, due to the influence of manufacturing level, cost and operating environment, flexible spacecraft are more prone to unpredictable failures. Once a failure occurs, the spacecraft will It will reduce or lose the intended function, which will have...

AI Technical Summary

Problems solved by technology

In view of the fact that the augmented fault diagnosis observer is simple in design and can estimate the original system state variables and fault signals at the same time, it has attracted extensive attention from academic and engineering circles at home and abroad. However, due to its own design problems, the observer dimension It is equal to the dimension of the original system state plus the dimension of the measurement output, which is difficult to design and realize in aerospace engineering

[0005] In terms of fault-tolerant control, the main research results are focused on the state feedback fault-tolerant control based on state observers. However, due to the coupling relationship between state estimation and fault estimation, it is difficult to design the state feedback matrix when designing a fault-tolerant controller, which increases the fault tolerance. The difficulty of controller design

Images