Fault-tolerant flight control method for fixed-wing unmanned aerial vehicle in control surface stuck state

Abstract

The invention is applicable to the technical field of fixed-wing unmanned aerial vehicles, and provides a fault-tolerant flight control method for a fixed-wing unmanned aerial vehicle in a control surface stuck state, which comprises the following steps of: acquiring a pitch angle, a roll angle, a yaw angle, a flight height and a speed of the unmanned aerial vehicle, comparing the pitch angle, the roll angle, the yaw angle, the flight height and the speed with expected values to calculate errors; a corresponding control law is adopted to control a corresponding execution mechanism; on the basis of a normal control law, a control mixer is added for the stuck state of an operation control surface, and the output of the normal control law is used as the input of the control mixer to execute the following control laws: the control law under the control surface stuck fault does not change the structure of an originally designed fractional order backstepping sliding mode controller; the advantages of an original controller can be reserved, the whole control system can be kept stable under the two fault conditions of rudder jamming and aileron jamming, and the fixed-wing unmanned aerial vehicle can adapt to different jamming angles to stably fly.

Description

technical field [0001] The invention relates to the technical field of fixed-wing unmanned aerial vehicles, in particular to a fault-tolerant flight control method for the stuck state of the rudder surface of the fixed-wing unmanned aerial vehicle. Background technique [0002] With the development of aerospace technology, fixed-wing UAVs have gradually entered people's lives due to their high flight altitude, strong endurance and transportation capabilities, and fast flight speed. Many scholars are committed to improving the flight performance of fixed-wing UAVs, but the kinematics model of fixed-wing is more complex, the coupling and nonlinearity are also stronger, and the flight control is more difficult. Especially when a fixed-wing UAV fails, the failure of the normal control law often leads to a crash. Since the flight environment of fixed-wing UAVs will change in a large range, resulting in perturbation of aerodynamic parameters and modeling errors, it will cause ins...

AI Technical Summary

Problems solved by technology

[0004]Since the fixed-wing UAV itself is an underactuated nonlinear system, the coupling between each state is relatively large, so its control is relatively complicated

Nowadays, the control technology of fixed-wing unmanned aerial vehicles and the control law reconstruction method under fault conditions are developing rapidly, but there are certain problems and defects in each control method, such as the PID control method for nonlinear multiple-input multiple-output The discomfort of the system, the weak anti-interference and robust characteristics of the backstepping control method, and the strong jitter that may exist in the backstepping sliding mode control method, etc.

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