Research On The Shimmy Stability Of Aircraft Landing Gear Base On The All-flexible Landing Gear Model

In the aircraft operation, aircraft wheel shimmy is a common and serious phenomenon, and it is a tremendous threat to the safety of aircraft flight. It has been a long time since the research on aircraft wheel shimmy started, but now this trouble cannot be avoided absolutely. There is an important theoretical significance and a practical engineering value to ensure the aircraft safety by further studying the problems such as the dynamic properties of aircraft lading-gear and the tire systems, especially the stability analysis of wheel shimmy.In this paper, the simulation method of shimmy stability analysis has been studied. Firstly, Virtual prototypes which contain all-flexible, rigid-flexible nose landing gear are established by the means of PATRAN software in ADAMS. And then, according to the load case of the landing gear shimmy test, virtual prototypes are tested to affirm their veracity. At last, some parametric tire properties are studied and the influences of the dynamic parameters of aircraft tire to the aircraft nose-wheel shimmy are observed, and then the analysis of shimmy stability is concluded.The formerly simulations are always based on rigid or rigid-flexible models, never seen by using all-flexible ones, and this way always has a lower precision and it cannot meet the higher requirement of precision.Comparing the results of the simulation of the formerly rigid or rigid-flexible models, the results show that the all-flexible landing gear model built in this paper are more veracious in line with the actual situation.The practical shimmy stability analysis researched in the paper can provide a reliable reference to the landing gear shimmy prevention and the improvement of landing gears structural design.