飞机前轮摆振影响因素分析

Analysis on the influencing factor of shimmy of the aircraft’s nose wheel

为了更好地分析飞机前轮摆振的影响因素,量化初始干扰因素值对临界摆振速度下飞机前轮摆振振幅的影响。基于线性假设,建立了飞机前轮摆振的动力学模型。在起落架结构参数固定的情况下,用特征值分析法求解出飞机摆振的临界滑跑速度。应用MATLAB/Simulink建立仿真框图,绘出飞机前轮摆角在临界滑跑速度下的时域曲线。在临界滑跑速度下,分析了各影响因素初始值对于飞机前进方向上稳定摆振振幅的影响,并提出初值影响因子的概念,计算得到各初始干扰因素的初值影响因子。最后,分析了在临界滑跑速度下,初始干扰因素的大小对飞机前轮稳定摆振频率的影响,并得出初始干扰因素的大小对飞机前轮摆振频率并无影响的结论。

In order to conduct an in-depth analysis on the shimmy of the aircraft’s nose wheel,the influence of initial interference factors on the amplitude of shimmy of the aircraft’s nose wheel at the critical taxiing speed is quantitatively analyzed.Based on the linear hypothesis,the related dynamic model is set up.When the landing gear’s structural parameters are fixed,the eigenvalue analysis is conducted to calculate the shimmy’s critical taxiing speed.MATLAB/Simulink is adopted to build up the simulation diagram,and the time-domain curve of the shimmy angle at the critical taxiing speed is identified.When the aircraft is moving forward at the critical taxiing speed,the influence of the initial values of different influencing factors on the amplitude of steady shimmy is analyzed.The concept of initial-value influencing factor is presented,and the related values are calculated.Finally,the influence of initial values on the frequency of shimmy of the aircraft’s nose wheel at critical taxiing speed is analyzed.It’s concluded that these initial interference factors have no effect on the frequency of shimmy of the aircraft’s nose wheel.