Methods and systems for controlling braking of a vehicle when the vehicle is stationary

• US 8,620,547 B2
• Filed: 07/15/2009
• Issued: 12/31/2013
• Est. Priority Date: 07/15/2009
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Monsere, Patrick J., Mui, Danny Y., Kidston, Kevin S.
• Primary Examiner(s): Tran, Khoi
• Assistant Examiner(s): PECHE, JORGE O
• Application Number:
  US12/503,655
• Publication Number:
  US 20110015845A1
• Time in Patent Office: 1,630 Days
• Field of Search: 701/22, 701/70, 701/78, 701/83
• US Class Current: 701/70
• CPC Class Codes: B60T 7/042 by electrical means, e.g. using travel or force sensors
• CPC Class Codes: B60T 8/885 using electrical circuitry

Abstract

A method for controlling braking of a vehicle includes the steps of calculating a first pressure based on a driver request, and providing pressure that does not exceed a predetermined pressure threshold if the vehicle is stationary and the first pressure is less than the predetermined pressure threshold.

Claims

1. A method for controlling braking of a vehicle during a braking event, the method comprising the steps of:

calculating, via a processor, a plurality of pressures during the braking event, each of the plurality of pressures calculated based on a different one of a plurality of driver requests detected via a sensor; and

providing, via the processor, pressure equal to a corresponding one of the plurality of pressure values if the vehicle is stationary and any of the plurality of pressures are less than a predetermined pressure threshold; and

providing, via the processor, pressure equal to the predetermined pressure threshold if the vehicle is stationary and none of the plurality of pressures are less than the predetermined pressure threshold.

2. The method of claim 1, wherein the vehicle has a wheel, and the method further comprises the steps of:

obtaining a wheel speed value from a wheel speed sensor; and

determining, via the processor, whether the vehicle is stationary based upon the wheel speed value.

3. The method of claim 1, further comprising the steps of:

providing, via the processor, pressure equal to an intermediate pressure value that is greater than the predetermined pressure threshold and less than the corresponding one of the pressure values., if each of the following conditions (a)-(b) are satisfied, namely;

(a) the vehicle is moving, and

(b) the vehicle has been moving for less than a predetermined amount of time.

4. The method of claim 1, further comprising the step of:

providing, via the processor, a constant pressure during a time interval, if conditions (a) and (b) are both satisfied;

(a) the plurality of pressures have each been greater than the predetermined pressure threshold; and

(b) the plurality of pressures are increasing during the time interval.

5. A system for controlling braking of a vehicle during a braking event, the system comprising:

a sensor configured to detect a plurality of driver requests during the braking event; and

a processor coupled to the sensor and configured to at least facilitate;

calculating a plurality of pressures during the braking event, each of the plurality of pressures calculated based on a different one of the plurality of driver requests; and

providing pressure equal to a corresponding one of the plurality of pressure values if the vehicle is stationary and any of the plurality of pressures are less than a predetermined pressure threshold; and

providing pressure equal to the predetermined pressure threshold if the vehicle is stationary and none of the plurality of pressures are less than the predetermined pressure threshold.

6. The system of claim 5, wherein the vehicle has a wheel, and the system further comprises:

a second sensor configured to obtain a wheel speed value, wherein the processor is further configured to determine whether the vehicle is stationary based upon the wheel speed value.

7. The system of claim 5, wherein the processor is further configured to at least facilitate:

providing a constant pressure during a time interval, if conditions (a) and (b) are both satisfied;

(a) the plurality of pressures have each been greater than the predetermined pressure threshold; and

(b) the plurality of pressures are increasing during the time interval.

8. The system of claim 5, wherein the processor is further configured to at least facilitate providing pressure equal to an intermediate pressure value that is greater than the predetermined pressure threshold and less than the corresponding one of the pressure values., if each of the following conditions (a)-(b) are satisfied, namely:

(a) the vehicle is moving, and

(b) the vehicle has been moving for less than a predetermined amount of time.

9. The system of claim 8, wherein the processor is further configured to at least facilitate providing pressure equal to the corresponding one of the plurality of pressures if the vehicle has been moving for more than the predetermined amount of time.