基于小车式起落架地面滑跑振动仿真分析

Simulation Analysis of Grand Rolling Vibration Based on Frame Landing Gear

飞机在地面滑跑过程中,由于起落架支柱和车架铰接,在着陆瞬间和刹车瞬间会引起车架剧烈的俯仰振动。以四轮小车式起落架为研究对象,通过对起落架结构、缓冲器、轮胎进行分析,采用LMS Virtual lab进行建模,基于Simulink模块建立PBM防滑刹车控制系统模型。仿真计算结果表明,落震引起的车架振动幅值大、能量高、持续时间短;刹车引起的车架振动幅值小、能量低、持续时间长。车架振动幅值随着陆速度增大而增大。增加辅助缓冲器的阻尼系数,可以有效减弱车架的俯仰振动;通过优化刹车控制律,减小初始时刻的刹车力矩,可使车架振幅降低10%。

When the aircraft is rolling on the ground,due to the articulation of the landing gear struts and the frame,the frame can cause violent pitching vibration at the moment of landing and braking.This paper takes the fourwheel trolley type landing gear as the research object,through the analysis of the landing gear structure,buffer and tires,LMS Virtual lab was used for modeling,and the PBM anti-skid brake control system model wass established based on the Simulink.The simulation calculation results show that the frame vibration caused by falling shock has a large amplitude,high energy and short duration,and the frame vibration caused by braking has a small amplitude,low energy and long duration.The vibration amplitude of the frame increases as the land speed increases.Increasing the damping coefficient of the auxiliary buffer can effectively reduce the pitch vibration of the frame.By optimizing the braking control law and reducing the initial braking torque,the frame amplitude can be reduced by 10%.