An Updating Method of Aero Tyre Model by Shimmy Test

Speed and oscillation frequency are two key factors that effect tyre lateral dynamic characteristics. Tyre models for previous landing gear shimmy analysis use stationary shape functions for the lateral tyre deformation which eliminate the effects of tyre speed and oscillation frequency. The lateral dynamic characteristics of tyre are studied by test on the dynamometer facility. The variation trend of amplitudes of the tyre self-aligning moment and lateral force with different speeds and oscillation frequencies is observed and fitted based on test results. The tyre model for landing gear shimmy analysis is updated by fitted coefficients. Nonlinear shimmy bifurcation analysis shows the shimmy unstable region enlarges when the tyre speed and frequency effects are considered. The method of updating tyre shimmy model based on test results could be used in landing gear shimmy analysis to improve the analysis accuracy.