Essentials of Vehicle Dynamics

(2.64)

$F_{y,\max }={\mu }_{y\mathrm{p}}·F_z$ (2.65)

(2.65)

Clearly, the peak friction coefficients are related to the road friction, with lower road friction leading to a proportional decrease of μ_xp and μ_yp. This suggests that the envelope of the general normalized shear force under combined slip between tire and road is a closed curve, with a maximum value μ_xp along the x-axis (pure slip in longitudinal direction) and a maximum value μ_yp along the y-axis (pure slip in lateral direction). In general, the drive force will be smaller than the brake force because ...