The Simulation Analysis On The Tire Stiffness And Tail-wheel Shimmy Of A Aircraft

When the helicopters can’t lift off because of heavy load, airport elevation or any other weatherconditions, it can take off by taxiing, just the same way as the aircraft. Therefore a new challengeraised up for the designers. That is the tail wheel shimmy, which is a critical problem we may oftenface in the design of landing gear system. In regard to the shimmy, the experts of home and abroadhave launched in-depth researches for a long period in the past, but still have not been able to avoid it.Tire is the only part transferring loading between ground and landing gear. Its mechanical property isone of the key features in the aircraft ground kinematics research. The stiffness of tire directlyinfluence drop shock and taxiing control performances. This paper foucs on the analysis of landinggear system, stiffness, shimmy and so on, which has an important theoretical significance andpractical engineering value to improve helicopter structure safety.In this paper, stiffness and shimmy stability have been analyzed by simulation method. In terms ofthe tire static stiffness analysis,3D FEA model of tire was established with Hypermesh and Abaqus,by taking principal elements into account, including the nonlinearities of material, geometry, contactand so on. Then the stiffness in radial and lateral directions are analyzed under different inflationpressure cases with Abaqus/Standard. The simulation dates and the theoretical dates are of the similartendency, which shows that the finite element analysis model can simulate the stiffness properties ofthe aircraft tire. In terms of shimmy analysis, virtual prototype which contains all-flexible landinggear was established by Hypermesh and LMS Virtual Lab Motion software. According to the case ofshimmy tests. the virtual prototype was analyzed by simulation, and did some researches on therelevant shimmy stability. The results show that the established tire and tail wheel landing gearshimmy models in this paper have a certain value in practice, and the research findings can provide afavorable guidance for the tire structure design and improve helicopter safety performance.