仿竹设计在无人机起落架结构中的应用

Application of Imitation Bamboo Design in Unmanned Aerial Vehicle Landing Gear Structures

应用于无人机的滑撬式起落架多使用弓形梁结构,几何特征上梁是一种细长弹性体,与竹子结构(具有较大细长比)相似。为了提高滑撬式起落架的结构性能,首先参考竹子的微观结构,设计了三种类维管束的仿生圆管,采用有限元法对仿生管轴向与径向碰撞吸能进行了仿真与计算;其次通过有限元静力学与动力学分析,对比了原结构与仿竹结构在相同载荷下的力学性能。仿真结果表明:静力学分析中,仿竹结构的最大应力相较于原结构降低约44%,并改善了弓形梁与滑筒连接处应力集中现象;动力学分析通过多工况模拟了起落架可能出现的平稳着陆与非平稳着陆,采用仿竹结构多工况的最大应力平均降低约22%,有效地提升了着陆性能。

The skid landing gear used in UAV often uses bow beam structure,and the upper beam is a kind of slender elastic body,which is similar to bamboo structure(with large slenderness ratio).In order to improve the structural performance of skid landing gear,First of all,refer to the microstructure of bamboo,three kinds of bionic circular tubes with similar vascular bundles are designed,the axial and radial collision energy absorption of bionic tube are simulated and calculated by finite element method;secondly through the finite element static and dynamic analysis,the mechanical properties of the original structure and the bamboo-like structure are compared under the same load.The simulation results show that in the static analysis,the maximum stress of the imitation bamboo structure is reduced by about 44%compared with the original structure,and the stress concentration at the joint between the bow beam and the sliding cylinder is improved.The possible smooth landing and non-smooth landing of the landing gear is simulated through multi-operating conditions in the dynamic analysis,and the maximum stress under multiple operating conditions of the bamboo-like structure is reduced by about 22%on average,it shows that the bamboo-like structure can effectively improve the landing performance.