US 5,631,836 A · Method of producing a straight-on travel signal

Abstract

Wheel speeds on each side of the vehicle are added, and the sums are subtracted to form a difference VXU which is time filtered to produce a filtered difference VXG. As long as VXU does not exceed VXG by more than a speed dependent threshold, a signal indicating straight line travel is produced. This signal can be cancelled when VXG exceeds a vehicle dependent threshold and is also blocked when the vehicle speed falls below a minimum, when the ABS is operating, or when the vehicle is decelerating. The signal indicating straight line travel accounts for tire tolerance and can be used to control vehicle dynamics, for example by preventing an increase in brake pressure or engine braking when the vehicle is travelling in a curve.

Claims7

Dependent claims

Method for controlling travel dynamics of a vehicle having right side wheels, left side wheels, brakes at said wheels, and an engine, said method comprising measuring the speed of at least one wheel on each side of the vehicle,

determining a difference VXU between the speed of at least one wheel on the left side and the speed of at least one wheel on the right side,
time-filtering said difference VXU to produce a time filtered difference VXG,
forming a difference VXU-VXG,
comparing said difference VXU-VXG to a first threshold, generating a signal indicating straight line travel when said difference VXU-VXG does not exceed said first threshold,
blocking said signal indicating straight line travel upon occurrence of at least one of (a) an ABS is operating, and (b) the vehicle is deceleratinq, and
controlling the traveling dynamics of the vehicle in accordance with whether or not the signal indicating straight line travel is present.

3 more elements

Dependencies are inferred from the claim text.

Method of producing a straight-on travel signal

Life of this patent

Method of producing a straight-on travel signal

Life of this patent

Abstract

Claims7