Method for operating a pre-crash sensing system in a vehicle having a countermeasure system

• US 6,498,972 B1
• Filed: 02/13/2002
• Issued: 12/24/2002
• Est. Priority Date: 02/13/2002
• Status: Expired due to Term

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Prakah-Asante, Kwaku O., Rao, Manoharprasad K., Strumolo, Gary Steven
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Hernandez, Olga
• Application Number:
  US09/683,774
• Time in Patent Office: 314 Days
• Field of Search: 701/45, 701/301, 280/734, 280/735, 180/170, 180/179, 180/232, 340/441
• US Class Current: 701/45
• CPC Class Codes: B60Q 1/381 with several light sources activated in sequence, e.g. to create a sweep effect
• CPC Class Codes: B60Q 1/46 for giving flashing caution signals during drive, other than signalling change of direction, e.g. flashing the headlights or hazard lights
• CPC Class Codes: B60W 30/09 Taking automatic action to avoid collision, e.g. braking and steering

Abstract

A control system (10) for an automotive vehicle (50) has a remote object sensor (18) that generates an object signal in the presence of an object. A vehicle trajectory sensor (34) generates a signal indicative of the vehicle traveling on a curved road. A vehicle speed sensor (32) generates a speed signal corresponding to the longitudinal speed of the vehicle. A controller (12) is coupled to the object sensor (18), the vehicle trajectory sensor, and the vehicle speed sensor. When the remote object sensor (18) indicates the presence of an object with a minimum cross section in a pre-defined decision zone meeting pre-defined relative velocity criteria, and when the vehicle speed is above a first threshold and below a second threshold, and when said vehicle trajectory signal indicates the vehicle traveling on a curved road with a radius of curvature above a threshold value, a vehicle safety countermeasure system (40) is deployed.

Claims

1. A method for operating a pre-crash sensing system having a countermeasure system comprising:

establishing a first speed threshold and a second speed threshold;

generating a speed signal corresponding to a vehicle speed;

disabling the countermeasure system when the vehicle speed is below the first threshold; and

disabling the countermeasure system when the vehicle speed is above said second threshold.

2. A method as recited in claim 1 further comprising generating a vehicle trajectory signal having a curved road indication;

and wherein disabling comprises disabling the countermeasure system when the vehicle speed is below the first threshold, above said second threshold or in response to said curved road indication.

3. A method as recited in claim 2 further comprising detecting a vehicle yaw rate signal and vehicle speed signal;

and wherein the curved road indication is a function of said vehicle yaw rate signal and vehicle speed signal.

4. A method as recited in claim 2 further comprising detecting a steering wheel angle signal;

and wherein the curved road indication is a function of said steering wheel angle signal.

5. A method as recited in claim 2 further comprising detecting a vehicle yaw rate signal and vehicle speed signal;

detecting a steering wheel angle signal; and

wherein the curved road indication is a function of said vehicle yaw rate signal, vehicle speed signal and steering wheel angle signal.

6. A method as recited in claim 1 further comprising establishing a decision zone in front of the vehicle.

7. A method as recited in claim 6 wherein establishing a decision zone in front of the vehicle comprises establishing a decision zone in front of the vehicle as a function of the first longitudinal threshold and the second longitudinal threshold.

8. A method as recited in claim 6 wherein establishing a decision zone in front of the vehicle comprises establishing a decision zone in front of the vehicle as a function of the first longitudinal threshold, the second longitudinal threshold and a lateral threshold which is a function of vehicle width.

9. A method as recited in claim 6 further comprising detecting an object within the decision zone;

and activating a countermeasure in response to detecting the presence of an object in the decision zone.

10. A method as recited in claim 9 wherein activating the countermeasure comprises pre-arming or deploying airbags, pre-tensioning a motorized belt pre-tensioner, and selectively changing a bumper height by activating a bumper height adjustment means in response to vehicle classification information.

11. A control system for an automotive vehicle having a vehicle body and a countermeasure system, said system comprising:

a remote object sensor generating an object signal in the presence of an object;

a vehicle trajectory sensor generating a signal indicative of the presence of a curved road;

a vehicle speed sensor generating a speed signal corresponding to the longitudinal speed of the vehicle body; and

a controller coupled to remote object sensor, said vehicle trajectory sensor and said vehicle speed sensor, when said remote object sensor indicates the presence of an object with a minimum cross section in a predefined decision zone meeting pre-defined relative velocity criteria, and said vehicle speed is above a first threshold and below a second threshold, and said vehicle trajectory sensor indicates a curved road with a radius of curvature above a threshold value, activating a countermeasure system.

12. A control system as recited in claim 11 wherein said vehicle trajectory sensor comprises a yaw rate sensor generating a yaw motion signal corresponding to a yaw motion of the vehicle body and a vehicle speed sensor.

13. A control system as recited in claim 11 wherein said vehicle trajectory sensor comprises a steering wheel angle sensor generating a steering wheel angle signal corresponding to a steering wheel angle position.

14. A control system as recited in claim 11 wherein said remote object sensor is selected from the group consisting of radar, lidar and vision systems.

15. A method for operating a pre-crash sensing system for an automotive vehicle having a countermeasure system comprising:

establishing a decision zone relative to the vehicle;

detecting an object within the decision zone;

establishing a first speed threshold and a second speed threshold;

generating a vehicle speed signal corresponding to a vehicle speed;

disabling the countermeasure system when the vehicle speed signal is below the first threshold or above said second threshold;

generating an object relative velocity signal corresponding to an object relative velocity within the decision zone;

disabling the countermeasure system when the object relative velocity signal is greater than a pre-established threshold;

generating a vehicle trajectory signal corresponding to a radius of curvature of the vehicle trajectory;

establishing a curved road signal threshold;

disabling the countermeasure system when the vehicle trajectory signal is less than the pre-defined curved road signal threshold; and

activating the countermeasure system in response to the controller actuation signal.

16. A method as recited in claim 15 further comprising determining countermeasure activation distance as a function of closing velocity;

determining an object distance; and

, disabling the countermeasure system when the object distance is greater than the countermeasure activation distance.

17. A method as recited in claim 16 further comprising determining an object cross-sectional area;

establishing a object cross-sectional area minimum threshold; and

, disabling the countermeasure system when the object cross-sectional area is less than the threshold value.

18. A method as recited in claim 17 wherein determining an object cross-sectional area comprises determining the object cross-sectional area with a vision system.

19. A method as recited in claim 17 wherein determining an object cross-sectional area comprises determining the object cross-sectional area with a scanning radar or lidar system.

20. A method as recited in claim 15 wherein generating a vehicle trajectory signal comprises generating a first radius of curvature signal from a yaw sensor and vehicle speed sensor;

generating a second radius of curvature signal from a steering wheel angle sensor;

establishing the vehicle trajectory signal as the lower of the first radius of curvature or the second radius of curvature signals.