Influence of the structural clearance on the shimmy characteristics of the landing gear during ground taxiing
RUAN Shuang1,2，ZHANG Ming1,3，NIE Hong1,2
1.College of Aerospace Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016，China；
2.State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing210016，China；
3.Ministerial Key Discipline Laboratory of Advanced Design Technology of Aircraft, Nanjing 210016，China
Abstract：Aiming at two common aircraft running states, i.e., anti-swing state and control state, a multi-degree-of-freedom vibration mechanical model of landing gear pendulum is established, and the mechanism of the influence of clearance on them is studied. Two different types of vibration mechanical mathematical models of landing gear pendulum with clearance are obtained. Through smoothing of non-smooth system and numerical analysis of multidimensional system. The results show that the shimmy frequency of landing gear will slightly increase under the shimmy reduction condition, and the structural Coulomb friction can weaken the continuous shimmy caused by structural clearance. For the control state, the frequency domain characteristics are analyzed by fast Fourier transform, and it is found that the coupling between the lateral bending and torsion of the strut is serious, and the rigidity between them directly determines the shimmy frequency of the landing gear. When there is a structural gap, the overall frequency of the landing gear will decrease, and eventually the system will gradually tend to a stable limit cycle oscillation state.
阮爽1，2，张明1，3，聂宏1，2. 结构间隙对起落架地面滑跑摆振特性影响分析[J]. 振动与冲击, 2024, 43(2): 234-243.
RUAN Shuang1,2，ZHANG Ming1,3，NIE Hong1,2. Influence of the structural clearance on the shimmy characteristics of the landing gear during ground taxiing. JOURNAL OF VIBRATION AND SHOCK, 2024, 43(2): 234-243.
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