Open AccessThe estimation of aircraft control system stability boundaries by the describing function method
Author(s) -
Iuliia Zaitceva,
Leonid Chechurin
Publication year - 2020
Publication title -
cybernetics and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.267
H-Index - 8
eISSN - 2226-4116
pISSN - 2223-7038
DOI - 10.35470/2226-4116-2020-9-2-117-122
Subject(s) - control theory (sociology) , describing function , parametric statistics , position (finance) , limit (mathematics) , stability (learning theory) , actuator , mode (computer interface) , signal (programming language) , function (biology) , mathematics , physics , computer science , control (management) , nonlinear system , mathematical analysis , statistics , finance , quantum mechanics , artificial intelligence , machine learning , evolutionary biology , economics , biology , programming language , operating system
In this paper, the conditions for periodic modes formation in the closed-loop pilot-vehicle system in the compensatory control mode are established. The case of high gain pilot task is considered under the conditions of a sudden disturbance, as well as under the influence of the system nonlinearities, such as actuator position and rate limit. Sinusoidal input describing function method and parametric resonance equation were used to determine the onset conditions for self-oscillations and forced oscillations. The case when this methods lead to erroneous results is established. The numerical limits of permissible pilot gain, time delay and reference signal at which unstable periodic modes do not arise are calculated.