Structure control coupling characteristic test analysis method suitable for digital flight control system

Abstract

The invention belongs to the technical field of aircraft structure control signals, and discloses a structure control coupling characteristic test analysis method suitable for a digital flight control system. The method comprises the steps: selecting a link with the lowest signal operation processing frequency as a loop breakpoint based on the signal transmission path analysis of a flight control sensor signal in the digital flight control system; performing quantitative testing on a final coupling effect after linear and nonlinear coupling superposition; and additionally arranging a second test point before aliasing of sensor signals, so that design basis is respectively provided for design of notch filters with two coupling structures. After the method is adopted, the signal aliasing and distortion characteristics of the all-digital flight control system adopted by the aerospace vehicle of the model in the signal transmission process can be clearly detected, the reason for obtaining the inconsistency between the open-loop stability margin and the closed-loop stability by adopting the traditional test method can be accurately positioned, and real open-loop frequency response characteristics are obtained.

Description

technical field [0001] The invention belongs to the technical field of aircraft structure control signals, and relates to an analysis method for aircraft structure control coupling characteristics, in particular to a test analysis method for structure control coupling characteristics applicable to digital flight control systems. Background technique [0002] Since the structure of the aircraft is not purely rigid, the flight control system sensor will sense the angular rate and overload signal caused by the elastic mode of the aircraft while sensing the motion of the rigid body of the aircraft, and form a control system composed of the flight control sensor-flight control computer-servo Actuator-elastic mode of aircraft structure-structure control coupling loop of flight control sensor. By carrying out the aircraft structure control coupling test on the ground, obtaining the aircraft structure control coupling characteristics and judging whether the aircraft structure contro...

AI Technical Summary

Problems solved by technology

However, when the aircraft flight control system is fully digitized, it is easy to introduce problems such as signal mixing and distortion, and a nonlinear control structure coupling loop appears.

The traditional test and analysis method relying on the frequency scanner cannot find the hidden nonlinear coupling path, resulting in the inability to completely solve the structural control coupling problem

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