Physical Understanding of Transient Generation of Tire Lateral Force and Aligning Torque

Abstract

Increasing vehicle performance requirements and virtualization of the development process require more understanding of the physical background of tire behavior, especially in transient rolling conditions with combined slip. The focus of this research is the physical description of the transient generation of tire lateral force and aligning torque. Apart from tire force and torque measurements, two further issues were investigated experimentally. Using acceleration measurement on the tire inner liner, it was observed that the contact patch shape of the rolling tire changes nonlinearly with slip angle and becomes asymmetric. Optical measurement outside and inside the tire has clarified that carcass lateral bending features both shear and rotation angle of its cross sections. A physical simulation model was developed that considers the observed effects. The model was qualitatively validated using not only tire force and torque responses but also deformation of the tire carcass. The model-based analysis explained which tire structural parameters are responsible for which criteria of tire performance. Change in the contact patch shape had a low impact on lateral force and aligning torque. Variation of carcass-bending behavior perceptibly influenced aligning torque generation.

Multi-body dynamics in vehicle engineering

“…Some of these tyre models have been extended to include the effect of tyre carcass elasticity and inflation pressure. [56][57][58][59] These additional features make the models more suitable for transient vehicle dynamics with combined slip, cornering and braking under extreme conditions, as well as riding over obstacles and kerb strikes. Figure 4 (a) and (b) show two types of brush models.…”

Study on the Self-Aligning Torque of BMW and Chevrolet During Driving and Its Influence on Vehicle Dynamic Performance

“…Besides, tire model is also important as the models for forces and torques are closely related to the idiosyncrasies of the tire. Elements like deformation of tire rubber, the in-plane belt deflection, and out-of-plane sidewall rotation are well-worth considering [8]. If we hope to research further on the contact between the tire and the road, the road adhesion coefficient is a great aspect to look at.…”

Improvement of steady-state PAC2002 under the sideslip and turn slip inputs based on the discrete theoretical tire model

“…3,8 Pacejka 3 developed an analytical brush model called TreadSim which considers the lateral, bending and yaw compliance of the belt/carcass in an empirical way, and rectangular contact patch at turn slip, but its iterative method is very simple, and when the stiffness of the carcass or belt is small, it is easy to lead to non-convergence. Different from Pacejka, literatures 22–29 regarded the belt/carcass as an elastic support infinite beam to express its deformation under force or moment in order to establish the relationship between design and model parameters, however, not including the turn input. Romano et al 30 give an application of the energy method to the governing PDEs of the brush models and analytical representation formulas for their solutions under spinning input, unfortunately, the simulation results are not given.…”