Patent ID: 7308373

Claim:
A method of determining a vehicle reference velocity (V ref ) of a motor vehicle that includes a vehicle wheel and that drives along a travel surface with friction between said vehicle wheel and said travel surface, said method comprising the steps: a) providing a maximally possible acceleration (a max ); b) determining ( 14 ) a measured velocity and a measured acceleration (a ist ) of said vehicle; c) checking ( 16 ) whether said measured acceleration (a ist ) exceeds said maximally possible acceleration (a max ); d) if said measured acceleration (a ist ) does not exceed said maximally possible acceleration (a max ), then determining ( 18 ) said vehicle reference velocity (V ref ) as being said measured velocity; and e) if said measured acceleration (a ist ) exceeds said maximally possible acceleration (a max ), then determining ( 24 ) a vehicle reference acceleration (a ref ) as: a ref =(1 −BKF )*( a max −a min )+ a min wherein: BKF =(a ist −a max )/(a top −a max ), a ref is said vehicle reference acceleration, a max is said maximally possible acceleration, a min is a minimal vehicle-specific acceleration based on said friction being infinite, a ist is said measured acceleration, a top is a maximal vehicle-specific acceleration based on said friction being at a lowest possible friction value, and determining ( 26 ) said vehicle reference velocity (V ref ) by integrating said vehicle reference acceleration (a ref ) over time.