某型无人机前起落架摆振分析

Analysis of Nose Landing Gear Shimmy of a UAV

起落架摆振是指飞机在着陆滑跑时前起落架机轮(或主起落架机轮)所发生的偏离机轮中立位置,同时在侧向和扭转方向出现剧烈的相互耦合运动的振动现象。在摆振设计中,应该选择合适的起落架参数,使得在整个滑跑参数范围内,机轮是摆振稳定的,并具有充分的稳定裕度。但是,单纯地依靠起落架本身的结构参数,往往不足以防止摆振。例如:稳定距增大到一定程度可以防止摆振,但对起落架受载和转弯操纵非常不利。迄今为止,防止摆振最有效的方法是减摆器装置。该文对某型无人机前起落架进行摆振分析,并验证减摆器的可行性。

Landing gear shimmy refers to the vibration phenomenon that the front landing gear wheel(or main landing gear wheel)deviates from the neutral position of the wheel during landing and taxiing,and there is violent mutual coupling movement in the lateral and torsional directions.In the shimmy design,appropriate landing gear parameters should be selected so that the wheel can shimmy stable and have a sufficient stability margin within the range.However,relying on the structural parameters of the landing gear itself is often insufficient to prevent shimmy.For example,increasing the stability distance to a certain extent can prevent shimmy,but it is very unfa‐vorable to the loading of the landing gear and the turning maneuvering.So far,the most effective way to prevent shimmy is the damper device.This article analyzes the nose landing gear of a certain type of UAV and verifies the feasibility of the damper.