摇臂式起落架缓冲机构动态分析与优化设计

Dynamic analysis and optimization design of a cushioning mechanism of articulated landing gear

为提高无人机起落架的缓冲性能,对摇臂式起落架缓冲机构进行动态分析与优化设计。建立滑跑过程数学模型,分析无人刹车操纵对起落架受力影响,并讨论缓冲机构性态及方案;利用多学科优化软件iSIGHT、集成动力学软件Adams对缓冲机构优化设计,以刹车工况缓冲要求及摆振遏制为约束条件,采用全域遍数法嵌套序列二次规划法对缓冲机构尺寸及弹簧刚度进行优化;对优化的起落架进行滑跑与静刚度试验。结果表明,起落架压缩位移满足预想要求,能量吸收提高71.5%。所用优化方法可为无人机摇臂式起落架设计、开发提供指导。

To improve the shock absorbing performance of UAV landing gear,a cushioning mechanism of articulated landing gear was dynamically analysed and optimally designed.Based on the establishment of mathematic model of UAV ground movement and the stress analysis of landing gear under braking control,the behavior and scheme of the cushioning mechanism were discussed.The software of multidisciplinary design optimization iSIGHT combined with the dynamic software Adams were applied to the optimization of cushioning mechanism.Then,taking the requirements of braking condition and shimmy containment as constraint,the size of the cushioning mechanism and the spring stiffness were optimized by using the method of point-by-point comparing at macrocosm combined with the sequential quadratic programming approach.The taxiing test and stiffness test of the optimized landing gear were carried out.The results show that the compression displacement meets the desired requirement and the efficiency of buffer is increased by 7 1 .5%.The analysis and optimization methods provide guidance for the design of UAV articulated landing gear.