Method and apparatus for monitoring wheel speeds
AssigneeRobert Bosch GmbH
InventorsWerner Urban, Thomas Braun
Life of this patent
Estimating the term…
Abstract
A method for monitoring wheel speeds, having the following steps: Determining the wheel speeds (S01), determining the wheel having the maximum wheel speed (S02), determining the wheel having the minimum wheel speed (S03), determining the speed difference between the maximum wheel speed and minimum wheel speed (S04), and comparing the speed difference to a threshold value (S05), deep snow or road conditions of comparable effect being inferred if the speed difference is greater than a threshold value and the slowest wheel has changed exactly once and the fastest wheel has changed exactly once or the slowest wheel has not changed and the fastest wheel has not changed and the speed difference between a driven axle and a non-driven axle exceeds a threshold value.
Claims15
A method for monitoring wheel speeds of a plurality of wheels, comprising the steps of:
- determining the wheel speeds;
- determining which of the plurality of wheels has a maximum wheel speed of the wheel speeds;
- determining which of the plurality of wheels has a minimum wheel speed of the wheel speeds;
- determining a first speed difference between the maximum wheel speed and the minimum wheel speed;
- comparing the first speed difference to a first threshold value;
- determining a second speed difference between a speed of a driven axle and a speed of a non-driven axle;
- and
- comparing the second speed difference to a second threshold value, wherein one of deep snow and a road condition of comparable effect are inferred if one of the following is true:
- a first state is present in which:
- the first speed difference is greater than the first threshold value, and
- a slowest of the plurality of wheels has changed exactly once and a fastest of the plurality of wheels has changed exactly once, and
- a second state is present in which:
- the slowest of the plurality of wheels has not changed and the fastest of the plurality of wheels has not changed, and
- the second speed difference is greater than the second threshold value.
An apparatus for monitoring wheel speeds of a plurality of wheels, comprising:
- an arrangement for determining the wheel speeds;
- an arrangement for determining which of the plurality of wheels has a maximum wheel speed of the wheel speeds;
- an arrangement for determining which of the plurality of wheels has a minimum wheel speed of the wheel speeds;
- an arrangement for determining a first speed difference between the maximum wheel speed and the minimum wheel speed;
- an arrangement for comparing the first speed difference to a first threshold value;
- an arrangement for determining a second speed difference between a speed of a driven axle and a speed of a non-driven axle;
- and
- an arrangement for comparing the second speed difference to a second threshold value, wherein one of deep snow and a road condition of comparable effect are inferred if one of the following is true:
- a first state is present in which:
- the first speed difference is greater than the first threshold value, and
- a slowest of the plurality of wheels has changed exactly once and a fastest of the plurality of wheels has changed exactly once, and
- a second state is present in which:
- the slowest of the plurality of wheels has not changed and the fastest of the plurality of wheels has not changed, and
- the second speed difference is greater than the second threshold value.
Dependencies are inferred from the claim text.