The problem of controlling the longitudinal motion of an aircraft (LA) is considered, taking into account the aero-elasticity of the wings, which is manifested by the most common and dangerous kind of flutter – the flexural-torsion wing flutter. It is pointed out that the problem of active (forced) suppression by means of control of the twist elastic vibrations of the wing, separated from the two-dimensional model of its flexural-torsional elastic oscillations, is fundamentally solvable in the framework of the automatic control system of the longitudinal motion of the aircraft due to the controllability of the process of the convolute elastic vibrations of the wing The control actions produced by the elevator. We propose a design scheme for the longitudinal motion of the aircraft, which takes into account the nonlinear torsional elasticity of the wings, and constructs a nonlinear mathematical model of the longitudinal motion of an aircraft, taking into account the elasticity of the wings, in the form of a nonlinear system of fifth-order differential equations. It is shown that taking into account the nonlinearities of the aerodynamic lift coefficient and the coefficient of torsional aeroelasticity leads to the appearance of essential power nonlinearities of the third and fourth degrees of growth with respect to the angles of attack and torsional deformations. Computer studies of the constructed adaptive control system for the nonlinear mathematical model of the longitudinal motion of an elastic aircraft, demonstrating its efficiency in suppressing nonlinear elastic oscillations of the wings of parametric and external perturbing influences.

Authors: V. V. Putov, V. N. Sheludko, V. F. Nguen, V. D. Than

Direction: Automation and Control

Keywords: Aircraft, longitudinal motion, nonlinear mathematical model, taking into account aeroelasticity, flexural-torsion wing flutter, majorizing function method, adaptive control systems by state, observer application, suppression of aeroelastic wings oscillation, wind disturbances of flight

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