Study On The Shimmy Stability Of Aircraft Landing Gear

Aircraft wheel shimmy is the one main cause of inducing aircraft malfunction in use. It has been a long time since the research on aircraft wheel shimmy started in and abroad, but till now the trouble can not be avoided. So thorough studying on shimmy problem has more significant for aircraft designer and user. Domestically, the shimmy stability was analyzed by self made program and rarely by big business software and this method always has a lower precision and a large error. However, the simulation method by big business software can calculate exactly, has clearly process, reliably results and good apply potential, so it is the mainly object to study in this paper.This paper studies shimmy stability mechanics modals based on the landing gears with single wheal or co-rotating dual wheels, uses shimmy stability analysis software shimmy view to calculate the stability of a certain type of aircraft landing gear and get the stability district. At the same time, the 3-D model of landing gear is established and is imported to the FEM software to make the structure analysis. From the analysis, the bending stiffness coefficient and torsional rigidity coefficient of the 3-D model is gotten for the shimmy simulation.In this paper, the simulation method of shimmy stability analysis is studied. Virtual prototypes which contain rigid, rigid-flexible nose landing gear and full aircraft shimmy prototyping are established. According to the load case of the landing gear shimmy test, virtual prototype is test to conform its veracity. Based on the prototype, the load case of the shimmy is analyzed, and then the shimmy stability curve of critical shimmy velocity versus damping is gotten, which will be contrasted with the result gotten from the analysis with the software shimmy view to make the conclusion. It is a good new way for analyzer to educe shimmy stability from the virtual prototype, because the precision model, the reliable result and using conveniently are the shining points of this method which is meaningful for shimmy avoiding in new aircrafts designing and for the maintenance of aircrafts in use.