起落架缓冲器摩擦特性建模与分析

Friction Modeling and Analysis of Landing Gear Buffer

在起落架工作时,若缓冲器上下支承与活塞杆之间的摩擦力过大,会使缓冲器无法正常被压缩,导致缓冲器卡滞失效,故需要对起落架缓冲器摩擦副的摩擦特性进行系统的分析和研究。以某型无人机主起落架为例,分析了半轴支柱式起落架构型缓冲器的载荷传递,通过理论计算得出了缓冲支柱上下支承处的径向力,并对油气式缓冲器的摩擦结构进行剖析,基于经典库伦+粘性+静摩擦+Stribeck模型,建立了临界摩擦系数计算模型,并结合起落架地面载荷计算,分析了缓冲器在静态和准静态受载下的摩擦特性。

The large friction between the upper and lower supports of the landing gear buffer and the piston rod will result in the buffer abnormally being compressed,leading to the buffer binding failure.Therefore,it is necessary to systematically analyze and study the friction characteristics of the landing gear buffer friction pair.Taking the main landing gear of an UAV as an example,this paper analyzes the load transfer of the half axle strut landing frame buffer,obtains the radial force at the upper and lower supports of the buffer strut through theoretical calculation,and analyzes the friction structure of the hydro pneumatic buffer.Based on the classical Coulomb+viscous+static friction+Stribeck model,the calculation model of the critical friction coefficient is established,and combined with the landing gear.The friction characteristics of buffer under static and quasi static loads are calculated and analyzed.