Patent ID: 6834221
Filing Date: 2004-12-21
Classification: B60K,B60T,G01P

Abstract:
A method of operating a motor vehicle with an engine, at least one drive axle with at least one wheel, the latter being in contact with a pavement surface, at least one torque transfer arranged in a power train between the engine and the at least one drive axle, and an automated transmission and at least one wheel rpm sensor device for detecting a wheel rpm rate of the at least one wheel; the method comprising the steps of:determining a transmission input rpm rate free of use of a transmission input rpm sensor and based on the at least one wheel rpm sensor and on a transmission ratio that is effective between the transmission output shaft and the transmission input shaft when a gear is engaged, wherein the transmission input rpm rate is determined by: calculating a substitute wheel rpm rate according to a predetermined characteristic; comparing the substitute wheel rpm rate to the detected wheel rpm rate; and determining whether the detected wheel rpm rate is sufficiently reliable to use in calculating a transmission input-rpm rate; and determining, based on the comparison between the substitute wheel rpm rate and the detected wheel rpm rate: whether the wheel is rolling on the pavement surface; whether the wheel is spinning while slipping on the pavement surface; whether the wheel is locked; whether the wheel rpm sensor device is functioning correctly; and whether the wheel rpm sensor device is functioning incorrectly.