Patent ID: 9694795
Date: 2017-07-04
CPC Classifications: B60T

Claim:
1. A method for determining road conditions during unbraked or braked travel of a vehicle a wheel-specific characteristic variable which is derived from a temporal change in wheel speed (φ′) detected, the method comprising: a) forming, by an anti-lock braking system (ABS) controller of the vehicle, a jerk signal (j) by computing for at least one vehicle wheel a second derivative of the wheel speed (φ′) detected by at least one wheel speed sensor of the vehicle, b) summing or integrating, by the ABS controller, a difference between an absolute value (|j|) of the jerk signal and a tolerance value with respect to time in order to compute a characteristic variable, c) determining, by the ABS controller, the road condition by comparing the characteristic variable with a vibration signal threshold value, and d) reducing, by the ABS controller, sensitivity for deciding when to apply a braking force to the at least one vehicle wheel when the vibration signal threshold value is exceeded by the characteristic variable.