Influence of thermal processes on tribological characteristics of tire contact with road surface and form of diagram φ(S) for different modes of wheel operation

The article considers not so widely known data from literature sources on the dependance of φ(S)-diagrams used in the theory of ABS and traction control systems on vehicle speed, wheel load conditions and the rate of change of these parameters. By switching from a single parameter (the dimensionless coefficient of sliding) to two independent parameters (the absolute speed of the wheel and the sliding velocity in the contact) the reason for the difference between traction and braking modes is shown.