An online identification method of aircraft aerodynamic characteristics based on backtracking adaptive algorithm

Abstract

The invention provides an aircraft aerodynamic characteristic on-line identification method based on a backtracking self-adaptive algorithm. The aircraft aerodynamic characteristic on-line identification method comprises steps: (1) equivalently transforming the product term of the inverse of a rotational inertia matrix and a moment vector in an aircraft angular velocity kinetic equation into a Phi<T>(k)Theta* form, carrying out discretization processing on the transformed product term, and obtaining an aircraft angular velocity difference equation; wherein Phi<T>(k) represents a signal vector,Theta* represents a parameter truth vector, and the parameter truth vector is a column vector including an aerodynamic characteristic parameter to be identified; (2) establishing a mathematical modelof an angular velocity estimation virtual system, and making an angular velocity estimation error and a parameter estimation error be Phi<T>(k)[Theta(k)-Theta*], wherein Theta(k) represents an estimated value of the parameter truth vector; (3) establishing a backtracking performance formula of the angular velocity estimation error, combining a backtracking updating rule to obtain Phi (k) in realtime, resolving the Theta(k) by means of the backtracking self-adaptive algorithm, making the angular velocity estimation error omega-wave(k) approach zero, and resolving the aerodynamic characteristic parameter to be identified according to the value of the Theta(k). The aircraft aerodynamic characteristic on-line identification method has a lower calculated amount and a lower demand on the computer, and has operability.

Description

technical field [0001] The invention relates to an online identification method of aircraft aerodynamic characteristics based on a backtracking adaptive algorithm, and belongs to the technical field of system identification and adaptive control. Background technique [0002] The aerodynamic characteristics of aircraft often need to rely on theoretical calculations or ground wind tunnel tests, but there are differences in both theoretical calculations and wind tunnel tests. For some important aerodynamic characteristics, there may even be differences between the ground test or calculation state and the actual flight state. The sign is opposite, and the opposite sign of important aerodynamic characteristics will often cause the aircraft to lose control due to the mismatch between the design of the control system and the aerodynamic characteristics. In order to prevent this from happening, it is generally necessary to avoid this situation from the perspective of overall design ...

AI Technical Summary

Problems solved by technology

[0004] There are many methods for online identification of aerodynamic parameters of traditional aircraft, but there are still few methods suitable for online identification of aerodynamic parameters of near-space vehicles

Compared with traditional aircraft, the dynamic model of near-space vehicles changes rapidly, and it is difficult to carry out online identification

At the same time, most of the existing aerodynamic parameter identification methods for near-space vehicles are about longitudinal parameters, which cannot be applied to identify the lateral aerodynamic parameters of the vehicle. Moreover, these algorithms are complex and computationally intensive, and cannot be applied to near-space vehicles. Online quick identification

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