Patent ID: 6971726

Claim:
A system for controlling the stability of a vehicle having wheels, including means for imparting a longitudinal force to a tire intended to roll on the ground, means for modulating the longitudinal force, and comprising a controller using at least a slip parameter G Opt corresponding to a predetermined value of a coefficient of friction μ, the system including means for performing the following operations: (a) on each activation of the means for imparting a longitudinal force to the tire, for at least two different levels “i” of the longitudinal force each corresponding to one slip G i , on condition that there is no loss of grip, determining values of the coefficient of friction μ i ; (b) determining a slope α i of a straight line passing through the origin and through (CT i , μ i ); (c) calculating coefficients A p by direct calculation or by a regression from a selected number of pairs with (α i , G i ) so as to model a variation curve α i =f(G i , A p ); (d) calculating the optimum slip G Opt by using a predetermined Invariant “Invt”; and (e) acting on the means for imparting a longitudinal force to the tire so as to maintain the slip at optimum value G Opt .