Nonlinear Dynamics

, Volume 57, Issue 3, pp 455–467

# Interaction of torsion and lateral bending in aircraft nose landing gear shimmy

• Phanikrishna Thota
• Bernd Krauskopf
• Mark Lowenberg
Original Paper

## Abstract

In this paper we consider the onset of shimmy oscillations of an aircraft nose landing gear. To this end we develop and study a mathematical model with torsional and lateral bending modes that are coupled through a wheel-mounted elastic tyre. The geometric effects of a positive rake angle are fully incorporated into the resulting five-dimensional ordinary differential equation model. A bifurcation analysis in terms of the forward velocity and the vertical force on the gear reveals routes to different types of shimmy oscillations. In particular, we find regions of stable torsional and stable lateral shimmy oscillations, as well as transient quasiperiodic shimmy where both modes are excited.

## Keywords

Aircraft dynamics Shimmy oscillations Mode interaction Quasiperiodic motion

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