垂直回收火箭可伸缩着陆腿展开的动力学仿真分析

可伸缩着陆腿是实现运载火箭垂直回收的有效途径。相比于着陆过程，火箭着陆腿展开过程涉及的动力学问题更值得特别关注。根据多体动力学方法建立可伸缩着陆腿的虚拟样机模型，针对展开过程开展仿真分析，研究了支腿结构柔性、腿节滑移摩擦力、气动罩气动力及过载等因素对展开时长和展开到位角速度两个关键展开特性指标的影响。结果表明，结构柔性对展开特性影响可忽略，过载对展开特性的影响最大，其次是气动罩气动力和腿节摩擦力。相关研究结果可为用于火箭垂直回收的可伸缩式着陆腿设计提供参考。

Dynamic Simulation and Analysis of the Deploying Process of Telescopic Landing Legs for Vertically-Recovered Rockets

Telescopic landing legs are practical approaches to realize vertical recovery for launch vehicles. Compared to the landing process, the deploying process of landing legs for vertically-recovered rockets involves dynamic problems that are worthy of more focus. Based on multi-body dynamics, the virtual prototype model of telescopic landing legs is created and simulated for the deploying process. The influences of structural flexibility, sliding friction between leg sections, aerodynamic drag of the fairing, and overload factor on the two key indexes for deploying characteristics, i.e., duration time and final angular velocity of deploying, are investigated intensively. Numerical results show that the effects of landing leg flexibility are neglectable; the overload factor has the maximum impact on the deploying process, while the aerodynamic drag of the fairing and leg section friction can exert relatively more minor effects. Related research results in this paper are expected to serve in the engineering development of landing legs for vertically-recovered rockets.