Method for avoiding false excitations of a slip control system of a brake system of a vehicle

Patent metadata

Field	Value
Publication number	US-10293797-B2
Application number	US-201615379672-A
Country	US
Kind code	B2
Filing date	Dec 15, 2016
Priority date	Jul 3, 2014
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

A method for avoiding false excitations of a slip control system comprises monitoring of a wheel speed signal for a predefined first monitoring time period for the start of a negative half-wave of an oscillation applied to a vehicle wheel, when a brake pressure gradient initiated by a brake start rises above a predetermined threshold. A ruck signal is derived from the wheel speed signal. An acceration signal is derived from the wheel speed signal during a predetermined second monitoring period. The wheel speed signal is monitored for a turning point of the ruck signal and a start of the acceleration signal. The oscillation imposed on the vehicle wheel is identified as a braking-induced vibration, and slip control is not carried out when the turning point of the ruck signal and the re-acceleration of the wheel are detected.

First claim

What is claimed is:

1. A method for avoiding false excitations of a slip control system of a brake system of a vehicle, the method comprising:
monitoring a wheel speed signal for at least one wheel for a predetermined first monitoring period for the start of a negative half-wave of an oscillation imposed on the vehicle wheel when a brake pressure gradient initiated by a brake application rises above a predetermined threshold;
deriving a nick signal from the wheel speed signal;
deriving an acceleration signal from the wheel speed signal during a predetermined second monitoring period following the point in time of the start of a detected negative half-wave of the speed signal;
monitoring the wheel speed signal for a turning point of the nick signal and a start of the acceleration signal indicating the re-acceleration; and
identifying the oscillation imposed on the vehicle wheel as a braking-induced vibration, wherein slip control of the vehicle wheel is not carried out when a turning point of the ruck signal and the re-acceleration of the wheel are detected.

2. The method of claim 1 , wherein monitoring of the wheel speed signal further comprises the step of determining a slip signal from the wheel speed signal and monitoring the speed of the vehicle, and identifying the oscillation imposed on the vehicle wheel as a braking-induced vibration when the slip signal does not reach a predetermined slip threshold.

3. The method of claim 1 , further comprising increasing the control thresholds of the slip control system upon the detection of a negative half-wave.

4. The method of claim 1 , wherein the oscillation imposed on the vehicle wheel is not identified as a braking-induced vibration when no turning point of the nick signal derived from the wheel speed signal is detected during a predetermined second time segment of the second monitoring period.

5. The method of claim 1 , wherein the oscillation imposed on the vehicle wheel is not identified as a braking-induced vibration if no re-acceleration of the acceleration signal derived from the wheel speed signal is detected during a predetermined first time segment of the second monitoring period.

6. The method of claim 5 , wherein the control thresholds are reset when a braking-induced vibration is not identified.

7. The method of claim 5 , wherein the second time segment is shorter than the first time segment.

8. The method of claim 5 , wherein taking into account a signal delay, the first time segment corresponds to half of the second monitoring period.

9. The method of claim 5 , wherein taking into account a signal delay, the second time segment corresponds to a quarter of the second monitoring period.

10. The method of claim 1 , wherein predeterming the threshold further comprises determining the threshold as a function of one of: the wheel pressure and a filtered signal of the wheel pressure.

Assignees

• Continental Teves Ag & Co Ohg

Inventors

• Kasten Manuel
• Kerber Henning
• Müller Jochen
• Roszyk Mario

Classifications

• B60T2210/14

  Rough roads, bad roads, gravel roads · CPC title

• B60T8/173 Primary

  Eliminating or reducing the effect of unwanted signals, e.g. due to vibrations or electrical noise · CPC title

• B60T8/172

  Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters {(B60T8/17551 takes precedence)} · CPC title

• B60T17/22

  Devices for monitoring or checking brake systems; Signal devices · CPC title