考虑减摆器非线性特性的前起落架摆振分析

飞机的前起落架摆振通常在飞机起飞或降落滑跑的过程中发生，对飞机的稳定性和操纵性产生危害，是一种严重的飞机故障。针对某型号无人机，基于动量矩定理，建立考虑起落架侧弯、扭转的摆振数学模型，讨论使用传统油液阻尼减摆器和电磁阻尼减摆器时不同的动力学模型。对于传统油液阻尼减摆器，采用等效线性模型，得到摆振临界稳定阻尼曲线的上下边界；而对于电磁阻尼减摆器的非线性模型，使用分岔分析理论确定系统的摆振稳定区域。结果表明：过大的减摆阻尼对摆振无法起到抑制的作用，得到控制参数平面上摆振的稳定区域，可为后续的起落架减摆设计提供参考。

Stability analysis of nose gear shimmy with Nonlinear Characteristics of Damper

The shimmy of the front landing gear of an aircraft usually occurs in the process of taking off or landing, which endangers the stability and maneuverability of the aircraft and is a serious aircraft fault. In this paper, based on the theorem of moment of momentum, a mathematical model of shimmy considering landing gear side bending and torsion is established for a certain type of UAV. The different dynamic models when using traditional oil damping damper and electromagnetic damping damper are discussed. For the traditional oil damping damper, the equivalent linear model is used to obtain the upper and lower boundaries of the critical stability damping curve. For the nonlinear model of electromagnetic damping damper, the bifurcation analysis theory is used to determine the shimmy stability area. It is shown that excessive shimmy damping can not suppress shimmy, and the stable region of shimmy on the parameter plane is obtained, It can provide some references for the design of landing gear shimmy reduction.