The National Transport University Bulletin

Abstract

The article presents the results of studies of the steered wheel kinematic and dynamic parameters depending on the knukle length during static steering. The object of the research is the static tire steering resistance torque. The purpose of the work is to determine the features of the steered elastic wheel movement during static steering depending on the knukle length and kingpin angles and to obtain analytical dependencies for determining the static torque of tire rotation resistance. The research method is analytical and experimental. It is proved that the phenomena which accompany the elastic steered wheel static turn and the nonsteered wheel movement along a curved trajectory are identical by themselves. During the static steered wheel rotation, as well as during the elastic wheel movement along a curved trajectory, there is a lateral displacement and disk twisting apropos to the tire contact patch. At the same time, the center of relative movement of the tire contact patch is within its limits, and as the knuckle length increases, it shifts to the patch edge. The center of transferable movement of the tire contact patch of the steered wheel during its static turn is the projection onto the support surface of the wheel rotation center, and its position is not significantly affected by the caster angle. The analysis of the experimental studies carried out on the bench which allowed to set discretely the knukle length as 0.225, 0.295, 0.365, 0.680, 0.820 m showed that the center of relative rotation of the tire contact patch is the knukle length function. Taking into account the studies mentioned above, the dependences for determining the maximum static tire turning resistance torque of the steered wheel tire rotation were specified. The results of the research can be useful to experts who work on improving the operational properties of wheeled vehicles, in particular, maneuverability, handleability and stability of movement.

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