Vehicle multi-stage integrated brake assist for a collision preparation system

• US 7,866,427 B2
• Filed: 07/08/2008
• Issued: 01/11/2011
• Est. Priority Date: 07/08/2008
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Zagorski, Chad T.
• Primary Examiner(s): Dickson; Paul N.
• Assistant Examiner(s): GOODEN JR, BARRY J
• Application Number:
  US12/168,973
• Publication Number:
  US 20100006363A1
• Time in Patent Office: 917 Days
• Field of Search: 180/167, 180/168, 180/169, 180/271, 180/274, 180/275, 180/175, 180/177, 701/45, 701/48, 701/96, 701/301
• US Class Current: 180/167
• CPC Class Codes: B60G 2800/222 during collision
• CPC Class Codes: B60T 2201/024 Collision mitigation systems
• CPC Class Codes: B60T 2201/03 Brake assistants
• CPC Class Codes: B60T 7/22 initiated by contact of vehicle, e.g. bumper, with an external object, e.g. another vehicle , or by means of contactless obstacle detectors mounted on the vehicle
• CPC Class Codes: B60W 2520/125 Lateral acceleration
• CPC Class Codes: B60W 2520/14 Yaw
• CPC Class Codes: B60W 2520/28 Wheel speed
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2540/18 Steering angle
• CPC Class Codes: B60W 30/08 Active safety systems predicting or avoiding probable or impending collision or attempting to minimise its consequences

Abstract

A motor vehicle multi-stage integrated brake assist (MSIBA) system, which can provide at least one brake assist level of a plurality of predetermined levels of brake assist (i.e., deceleration) less than or greater than the required amount of braking (i.e., deceleration) calculated by the MSIBA to avoid a collision with an obstacle at the time the driver initiates braking, but allows the driver to increase or remove the provided predetermined level of brake assist.

Claims

1. A method for multi-stage integrated brake assist for a collision preparation system of a motor vehicle, comprising the steps of:

determining a necessary deceleration of the motor vehicle to avoid an impact;

detecting driver selected braking of the motor vehicle; and

setting a braking assist responsive to the detecting of driver selected braking if;

the driver selected braking meets at least one predetermined braking threshold of a range of predetermined braking thresholds and the driver selected braking is less than the necessary deceleration;

wherein the detecting of driver selected braking comprises;

detecting at least one brake pedal position threshold; and

detecting at least one brake pedal velocity threshold;

wherein the at least one predetermined braking threshold comprises the driver selected braking meeting simultaneously the at least one brake pedal position threshold and the least one brake pedal velocity threshold;

wherein the detecting of brake pedal position comprises detecting any of a plurality of position thresholds of respective percents of full brake pedal travel, and the detecting of brake pedal velocity comprises detecting any of a plurality of velocity thresholds of respective percents of full brake pedal travel per unit of time;

wherein for each position threshold is a corresponding velocity threshold which in combination comprise a respective braking threshold, wherein each respective braking threshold corresponds to a respective brake assist level, and wherein each brake assist level comprises a respective amount by which the braking assist is set in said step of setting;

wherein the range of predetermined braking thresholds comprises brake assist levels ranging from a lowest to a highest in monotonically increasing order; and

wherein the brake assist levels comprise;

a level 1 brake assist level comprising greater than or equal to about 30 percent of full brake pedal position and greater than or equal to about 120 percent of full brake pedal travel per second, wherein the braking assist is set to substantially 80 percent of the necessary deceleration; and

a level 2 brake assist level comprising greater than or equal to about 50 percent of full brake pedal position and greater than or equal to about 150 percent of full brake pedal travel per second, wherein the braking assist is set to substantially 90 percent of the necessary deceleration.

2. The method of claim 1, further comprising:

detecting whether an obstacle in the path of the motor vehicle in relation to the movement of the motor vehicle is such that a predetermined Collision Judgment Line is crossed, wherein in said step of setting, if the driver selected braking meets at least the predetermined braking threshold for the lowest threshold, then the highest brake assist level is used to set the braking assist in said step of setting.

3. The method of claim 1, wherein the brake assist levels further comprise:

a level 3 brake assist level comprising greater than or equal to about 70 percent of full brake pedal position and greater than or equal to about 200 percent of full brake pedal travel per second, wherein the braking assist is set to substantially 105 percent of the necessary deceleration.

4. The method of claim 3, further comprising:

detecting whether an obstacle in the path of the motor vehicle in relation to the movement of the motor vehicle is such that a predetermined Collision Judgment Line is crossed, wherein in said step of adjusting, if the driver selected braking meets at least the predetermined braking threshold for the lowest threshold, then the highest brake assist level is used to set the braking assist in said step of setting.

5. An apparatus for braking a motor vehicle, comprising:

a braking system;

a collision preparation system interfaced with said braking system;

a collision preparation system braking adjustment controller interfaced with said braking system;

a multi-stage integrated brake assist system interfaced with said collision preparation system and said braking adjustment controller; and

at least one source of data available to said multi-stage integrated brake assist system, said data comprising brake pedal position, brake pedal velocity, and braking request of the driver;

wherein the multi-stage integrated brake assist system increases the braking request of the driver through the collision preparation system braking adjustment controller in response to the brake pedal position and the brake pedal velocity meeting at least one predetermined threshold responsive to said data;

wherein the multi-stage integrated brake assist system responds to said data according to whether at least one brake pedal position threshold and at least one brake pedal velocity threshold have been simultaneously met;

wherein the at least one brake pedal position threshold comprises a plurality of position thresholds of respective percents of full brake pedal travel, and the at least one brake pedal velocity threshold comprises a plurality of velocity thresholds of respective percents of full brake pedal travel per unit of time;

wherein for each position threshold is a corresponding velocity threshold which in combination comprise a respective braking threshold, wherein each respective braking threshold corresponds to a respective brake assist level;

wherein each brake assist level comprises a respective amount by which the braking request of the driver is increased by said multi-stage integrated brake assist system;

wherein the brake assist levels range from a lowest to a highest in monotonically increasing order; and

wherein the brake assist levels comprise;

a level 1 brake assist level comprising greater than or equal to about 30 percent of full brake pedal position and greater than or equal to about 120 percent of full brake pedal travel per second, wherein the braking request of the driver is increased to substantially 80 percent of the necessary deceleration to avoid a collision based upon the data; and

a level 2 brake assist level comprising greater than or equal to about 50 percent of full brake pedal position and greater than or equal to about 150 percent of full brake pedal travel per second, wherein the braking request of the driver is increased to substantially 90 percent of the necessary deceleration to avoid the collision.

6. The apparatus of claim 5 wherein if the collision preparation system detects an obstacle in the path of the motor vehicle in relation to the movement of the motor vehicle is such that a predetermined Collision Judgment Line is crossed, and if the data meets at least the predetermined braking threshold for the lowest threshold, then said multi-stage integrated brake assist system uses the highest brake assist level to increase the braking request of the driver.

7. The apparatus of claim 6 wherein said multi-stage integrated braking system increases the braking request of the driver if:

the braking request of the driver as determined from the data meets at least one braking assist level, the requested braking of the driver is less than the deceleration necessary to avoid a collision as determined from the data, and the braking request of the driver does not exceed the highest brake assist level.

8. The apparatus of claim 5 wherein the brake assist levels further comprise:

a level 3 brake assist level comprising greater than or equal to about 70 percent of full brake pedal position and greater than or equal to about 200 percent of full brake pedal travel per second, wherein the braking request of the driver is increased to substantially 105 percent of the necessary deceleration to avoid the collision.

9. The apparatus of claim 8 wherein if the collision preparation system detects an obstacle in the path of the motor vehicle in relation to the movement of the motor vehicle is such that a predetermined Collision Judgment Line is crossed, and if the data meets at least the predetermined braking threshold for the lowest threshold, then said multi-stage integrated brake assist system uses the highest brake assist level to increase the braking request of the driver.

10. The apparatus of claim 9 wherein said multi-stage integrated braking system increases the braking request of the driver if:

the braking request of the driver as determined from the data meets at least one braking assist level, the requested braking of the driver is less than the deceleration necessary to avoid a collision as determined from the data, and the braking request of the driver does not exceed the highest brake assist level.