Elements of road-tyre interaction Seminar

The main function of a car tyre is to provide adequate traction in wet and dry driving conditions.  However in recent years it has been realised that the noise and energy loss from driven tyres represents a significant social and environmental problem. To make quieter, and more energy efficient tyres or roads, while maintaining road grip, it is first necessary to understand the underlying physics of the road-tyre interaction. The presentation witll describe some of the progress made in this area.

The contact forces beneath loaded tyre will be given, with the relationship to noise and friction. The two interacting components will be described, i.e. a wave model of a car tyre that covers the range from 0-3kHz, for normal and tangential excitation; and a description of the road surface that covers the full bandwidth for noise, vibration and friction. Using the surface model in conjunction with the dynamic rubber properties, the basic friction model for hysteresis friction will be presented. The results are compared with measurements and other friction mechanisms, in particular the contribution of atmospheric pressure.