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A unified non-steady non-linear tyre model under complex wheel motion inputs including extreme operating conditions

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Abstract

This study is to describe the transient force and moment characteristics of tyres involving large lateral slip, longitudinal slip, turn-slip and camber, and to develop a dynamic tyre model applicable to vehicle dynamic simulation and control for extreme operating conditions. Based on the steady state USES tire model [4,6], the effective slip ratios and quasi-steady concept are introduced to represent the non-linear dynamic tire properties in large slip cases. A high-order non-steady tyre model is presented. Special attention has been paid on the relationship between turn-slip and camber. Various kinds of experiments are performed to verify the tire model.

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Theoretically a unified tire model with non-isotropy of friction is presented as a foundation for studying the key features of a reasonable expression of tire shear force and alignment torque under combined slip conditions. The effects of longitudinal force and pressure distributionon tire cornering stiffness are analyzed. A unified semi-empirical tire model with high accuracy and convenience in vehicle dynamics simulation is proposed. Some experimental validations are shown.
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