Shimmy can reduce the service life of the nose
landing gear, affect ride comfort, and even cause fuselage damage leading to
aircraft crashes.Taking a light aircraft as the research object, the
torsional freedom of landing gear around strut axis and lateral deformation of
tire are considered.Since the landing gear shimmy is a nonlinear system,
a nonlinear mechanical model of the front landing gear shimmy is established.
Sobol index method is proposed to analyze the influence of structural
parameters on the stability region of the nose landing gear, and Routh-Huritz
criterion is used to verify the reliability of the analysis results of Sobol
index method. We analyse the effect of torsional stiffness of strut, caster
length, rated initial tire inflation pressure, rake angle, and vertical force
on the stability region of theront landing gear. And the research shows that
the optimization of the torsional stiffness of the strut and the caster length
of the nose landing gear should be emphasized, and the influence of vertical
force on the stability region of the nose landing gear should be paid attention
to.
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