Aircraft prediction and correction composite guidance method based on sliding mode disturbance observer

Abstract

The invention relates to an aircraft prediction and correction composite guidance method based on a sliding mode disturbance observer, wherein the method comprises the following steps: 1, building an aircraft three-degree-of-freedom nonlinear model containing multi-source disturbance according to the nonlinear kinematics and dynamics characteristics of a hypersonic aircraft, and carrying out representation of the multi-source disturbance; 2, designing the sliding mode disturbance observer to carry out rapid online estimation on lumped disturbance; 3, respectively designing a longitudinal guidance law and a lateral guidance law according to the flight state and control input of the aircraft at the current moment, and converting heat flux density, overload and dynamic pressure constraints into heeling angle amplitude constraints by using quasi-equilibrium gliding conditions and disturbance estimated values to ensure that process constraints are met; and 4, designing a composite guidance law according to the disturbance estimation value and the output value of the prediction correction guidance, and finally completing the design of the guidance method. The method is high in anti-disturbance capability, high in guidance precision and suitable for various types of hypersonic aircrafts without power reentry.

Description

technical field [0001] The invention relates to the field of hypersonic aircraft guidance, in particular to an aircraft prediction and correction composite guidance method based on a sliding mode disturbance observer. Background technique [0002] A hypersonic vehicle is an aircraft with a flight speed higher than Mach 5, and its flight altitude is between ordinary aircraft and orbiter (20-100km). This type of aircraft has the advantages of fast speed, long range, and high maneuverability, and has important application prospects in military and civilian fields. Due to the complexity of the vehicle itself and the flight environment, the guidance and control of hypersonic vehicles face many challenges, mainly in the aspects of strong nonlinearity, fast time variation, strong coupling and uncertainty. The flight span of a hypersonic vehicle is huge, and there are huge differences in the aerodynamic characteristics of high and low altitudes, which eventually lead to strong unce...

AI Technical Summary

Problems solved by technology

[0008] The technical problem solved by the present invention is to provide a sliding mode disturbance observer based on the guidance problem of unpowered hypersonic vehicle re-entry section with atmospheric density uncertainty and aerodynamic parameter uncertainty, to overcome the deficiencies of the prior art The aircraft prediction and correction composite guidance method realizes the rapid estimation and compensation of complex disturbances, adopts a set of guidance strategies to generate guidance instructions, and ensures that process constraints such as heat flux density, overload, and dynamic pressure are met, and improves the accuracy of the guidance process of hypersonic aircraft Sexuality, autonomy and anti-interference ability

Images