*2.1. Tire Slip Characteristics*

Tire slip characteristics are described by curves that characterize the longitudinal and lateral forces that are transmitted onto the road by the tire at various slips of the tire. The tire slip characteristic shown in Figure 1 presents a typical course of the longitudinal and lateral forces.

The longitudinal forces Fx are the braking and driving forces that a tire can transfer onto the road under various slip values. The lateral forces Fy are forces that a tire transfers onto the road when the vehicle is changing direction. Figure 1 demonstrates the size of the braking (driving) force and the lateral force that a tire can transfer onto the road at various slips [22,23].

**Figure 1.** Slip characteristics of tires with radial construction.

Slip λ is calculated according to the equation:

$$\lambda = \frac{\upsilon - \omega \times R\_{\omega}}{\upsilon} = 1 - \frac{\omega \times R\_{\omega}}{\upsilon} \tag{1}$$

where:


*R*ω is tire radius.
