A new tire model for aircraft landing gear dynamics

The aircraft landing gear is, by nature of its function and subsequent design, a complex, multi-degree-of-freedom system. The stability of such a system requires further study, particularly at the tire-runway boundary condition. Presented here is an extensive literature search on previous work concerning the shimmy phenomenon, followed by a course of work defining the role which the tire plays. The tasks performed included deriving and discretizing the equations of motion for the tire, developing an empirical model for the tire's inflation loading characteristics, loading and rolling the tire in the vertical plane, laterally deflecting and twisting the tire's vertical plane, and discussing interaction of the tire model with landing gear dynamics models. Given identical inflation pressure and target vertical load, the dominant factor on out-of-plane stability response is the nonlinear softening effect of increasing air vehicle velocity. The most significant contribution of this work is the development of the tire model into a physically accurate, computationally inexpensive and fast desktop computer product for use as a landing gear system component in air vehicle ground operations simulations.