Shimmy vibration analysis of aircraft landing gears

Shimmy vibration is a very important type of motion in the landing gear system during either the takeoff or landing of an aircraft. Energy input for this type of vibration is provided from the kinetic energy of the forward motion of the aircraft. As a result, this energy initiates a self-excited type of vibration in the wheels that may lead to instabilities. An attempt is made to develop a dynamical model for the aircraft nose gear to investigate its transient response for the lateral deviations and shimmy angles. Variations of different design parameters-namely, the energy absorption coefficient of the shimmy damper and the location of the gravity center of the landing gear-are studied. Results are presented graphically to facilitate the investigation of landing gear shimmy vibration.