Effect of Shimmy Oscillation on Dynamic Response of Unmanned Aircraft Landing Gears

Abstract

Unmanned airplanes are extensively useful in several fields, particularly in defense newlineand military. Development of such aircrafts with landing gears attachments is critical newlineaspect. The design stage of landing gears involves in evaluating its dynamic stability to newlineensure effective ground operations. During takeoff, taxiing and landing, aircrafts operates newlineon runways leads to self-excited shimmy oscillation of landing gear, which can potentially newlineharm its structure and reduce its useful life. Landing gear self-excited shimmy is a critical newlinedynamic stability problem to overcome by the aircraft designers. It is a combined lateral newlineand yaw oscillations governed by landing gear dynamics and tire characteristics. Shimmy newlineoscillations generally arise due to low torsional stiffness, higher runway roughness, newlinefriction, free play and tire forces. Investigation of shimmy oscillations of landing gear is newlinemore complex because it is multi degrees of freedom nonlinear dynamic system. newlineTo analyze stability of the aircraft during ground maneuvering it is significant to newlineunderstand the behavior of landing gears. For this purpose, suitable mathematical models newlineare required to precisely assess the stability of the system and the parameters governing newlineshimmy oscillation. This work deals with the development of two non-linear mathematical newlinemodels to study shimmy oscillations of landing gears newline