Dynamic Analysis of Nose Landing Gear Shimmy Considering Strut Height and Experiment on the Test Platform

This study investigates the influence of strut height on the shimmy stability of aircraft nose landing gear through both theoretical modeling and experimental validation. A nonlinear dynamic model incorporating strut height is established to derive analytical expressions for the critical shimmy speed. The effects of key structural parameters, including lateral bending stiffness, torsional stiffness, damping, diagonal brace positioning, and shimmy damper installation height, are systematically analyzed. The results indicate that increasing strut height significantly reduces lateral bending stiffness and damping, leading to a lower critical shimmy speed and reduced stability. To validate the theoretical findings, a nose landing gear shimmy test platform was developed, and high-precision laser vibrometry was used to capture the dynamic responses under different taxiing speeds. The experimental results align closely with theoretical predictions, confirming the accuracy of the model and providing quantitative insights into the relationship between strut height and shimmy stability. This research offers valuable theoretical guidance and engineering recommendations for optimizing landing gear designs, particularly for aircraft with high-strut configurations.