A non-linear self-adaptive flight control method

Abstract

The invention relates to a non-linear self-adaptive flight control method belonging to the technical field of near-space aircraft flight control. According to the invention, with regard to problems of indeterminate parameters in vertical control of near-space aircrafts, and with consideration given to advantages of sliding-mode control over non-linear system control and the feature that interval second-type fuzzy control with nondeterminacy fuzzy sets is especially suitable for solving problems of nondeterminacy, a second-type fuzzy control system is combined with sliding-mode control and self-adaptive control to design a flight controller to enable the flight controller to have better control performance. The stability and robustness of the near-space aircrafts are raised.

Description

Technical field [0001] The invention relates to a nonlinear adaptive flight control method, belonging to the technical field of flight control methods for near-space aircraft. Background technique [0002] With the development of the aerospace industry, research in aircraft-related fields has been increased at home and abroad. As an important part of aircraft, flight control systems have attracted the attention and attention of scholars from various countries. The diversity and variability of flight missions has led to the derivation of various new types of high-complexity aircraft, which in turn imposes higher and higher requirements on flight performance. The flight environment of the near-space vehicle and its own complex and changeable aerodynamic characteristics have brought many technical difficulties to the design of the flight control system. [0003] Many experts and scholars at home and abroad have conducted in-depth research on the uncertainty of near-space vehicles and...

AI Technical Summary

Problems solved by technology

Foreign Sigthorsson et al. proposed a method of robust linear output feedback control to achieve good speed and altitude tracking of air-breathing aircraft with uncertainty under multi-flight conditions, but the method used is based on linear control. The large envelope flight of the aircraft has great limitations and lacks engineering practical significance

Zhang et al. proposed a method combining terminal sliding mode and second-order sliding mode to solve the problem of hypersonic vehicle parameter uncertainty and achieve better results, but in this method, uncertain disturbances are assumed is a constant value, so the actual control effect will be affected

In addition, the continuous high-order sliding mode control method is also used to overcome the uncertainty of aerodynamic parameters, and effectively overcome the chattering problem of sliding mode control, but the nonlinear model of the hypersonic vehicle needs to be simplified when designing the controller. It is also not conducive to the realization of the project

To sum up, for the uncertainty problem, although there are many literatures that have been studied, there is no comprehensive and better solution

Images