System and method of regulating manual control of a vehicle in a sliding condition

• US 6,672,689 B1
• Filed: 06/28/2002
• Issued: 01/06/2004
• Est. Priority Date: 06/28/2002
• Status: Expired due to Term

• Current Assignee: Continental Automotive Systems, Inc. (Continental AG)
• Original Assignee: Continental Teves Incorporated (Continental AG)
• Inventors: Bauer, Geoffrey Burke
• Primary Examiner(s): Schwartz, Christopher P.
• Assistant Examiner(s): KRAMER, DEVON C
• Application Number:
  US10/184,244
• Publication Number:
  US 20040000814A1
• Time in Patent Office: 557 Days
• Field of Search: 303/3, 303/7, 303/9.62, 303/125, 303/133, 303/139, 303/140, 303/144, 303/146, 303/147, 303/154, 303/166, 303/167, 303/20
• US Class Current: 303/146
• CPC Class Codes: B60T 2230/02 Side slip angle, attitude angle, floating angle, drift angle
• CPC Class Codes: B60T 8/17552 responsive to the tire sideslip angle or the vehicle body slip angle

Abstract

The present invention involves a system and method of regulating manual control for a driver of a vehicle during a sliding condition of the vehicle having an electronic stability program using a stability control system. The method includes recognizing the vehicle in a sliding condition and determining whether the vehicle is manually controllable in the sliding condition. The method further includes adjusting the electronic stability program, if the vehicle is determined to be manually controllable, and activating the stability control system to control the vehicle when the vehicle is not manually controllable. The method further includes applying a compensated brake pressure on the vehicle based on the activation of the stability control system.

Claims

1. A method of allowing manual control for a driver of a vehicle during a sliding condition of the vehicle having an electronic stability program using a control system, the method comprising:

recognizing the vehicle in a sliding condition;

determining whether the vehicle is manually controllable in the sliding condition;

adjusting the electronic stability program and preventing operation of the control system, if the vehicle is determined to be manually controllable; and

activating the control system to control the vehicle, when the vehicle is not manually controllable;

by

applying a compensated brake pressure based on the activation of the control system.

2. The method of claim 1 wherein recognizing the vehicle in the sliding condition includes:

sensing a rate of change of a vehicle side slip angle of the vehicle;

comparing the rate of change of the vehicle side slip angle to a minimum rate of change of the side slip angle;

sensing a vehicle yaw rate of the vehicle;

determining a yaw rate error based on the vehicle yaw rate;

comparing the yaw rate error to a minimum yaw rate error; and

determining that the vehicle is in the sliding condition, if the rate of change of the vehicle side slip angle is greater than a minimum side slip angle and the vehicle yaw rate is greater than a minimum yaw rate.

3. The method of claim 1 wherein determining whether the vehicle is manually controllable includes:

determining whether the vehicle is within a controllable range;

determining whether the vehicle is being steered toward a path on which the vehicle is sliding;

determining whether the vehicle is being steered at about a rate which the vehicle is sliding;

determining whether a rate of rotation of the vehicle in the sliding condition is within a predetermined range; and

recognizing that the vehicle is manually controllable, if the vehicle is within the controllable range, if the vehicle is being steered toward the path on which the vehicle is sliding, if the vehicle is being steered within the rate at which the vehicle is sliding, and if the rate of rotation of the vehicle in the sliding condition is within the predetermined range.

4. The method of claim 3 wherein determining whether the vehicle is within the controllable range, the controllable range includes sensing a rate of change of the vehicle side slip angle of the vehicle;

comparing the rate of change of the vehicle side slip angle to a maximum side slip angle;

sensing a vehicle yaw rate of the vehicle;

determining a yaw rate error based on the vehicle yaw rate;

comparing the yaw rate error to a maximum yaw rate error of the vehicle; and

recognizing that the vehicle is within the controllable range, if the rate of change of the vehicle side slip angle is less than a maximum rate of change of the side slip angle and the vehicle yaw rate error is less than the maximum yaw rate error.

5. The method of claim 3 wherein determining whether the vehicle is being steered toward the path on which the vehicle is sliding includes sensing a steering wheel angle of the vehicle;

determining a rate of change of the steering wheel angle;

sensing a vehicle side slip angle;

determining a rate of change of the vehicle side slip angle;

comparing the rate of change of the steering wheel angle to the rate of change of the vehicle side slip angle; and

recognizing that the vehicle is being steered toward the path on which the vehicle is sliding, if the rate of change of the steering wheel angle is about the same as the rate of change of the vehicle side slip angle.

6. The method of claim 3 wherein determining whether the vehicle is being steered at the rate at which the vehicle is sliding includes:

sensing a vehicle side slip angle of the vehicle;

determining a rate of change of the vehicle side slip angle;

sensing a vehicle steering wheel angle of the vehicle;

determining a rate of change of the steering wheel angle;

comparing the rate of change of the steering wheel angle to the rate of change of the vehicle side slip angle and a predetermined active band angle;

recognizing that the vehicle is being steered within the rate at which the vehicle is sliding, if;

the rate of change of the steering wheel angle is greater than the rate of change of the vehicle side slip angle minus the predetermined active band angle; and

the rate of change of the steering wheel is less than the rate of change of the vehicle side slip angle plus the predetermined active band angle, defining a rate of change of the steering wheel angle range within which the vehicle is manually steered.

7. The method of claim 3 wherein determining whether the rate of rotation of the vehicle in the sliding condition is within the predetermined range includes:

sensing a vehicle steering wheel angle of the vehicle;

comparing the vehicle steering wheel angle with a maximum steering wheel angle;

comparing the vehicle steering wheel angle with a minimum steering wheel angle; and

recognizing that the rate of rotation of the vehicle in the sliding condition is within the predetermined range, if;

the vehicle steering wheel angle is less than the maximum steering wheel angle; and

the vehicle steering wheel angle is greater than the minimum steering wheel angle, defining a rate of rotation range of the vehicle being manually controlled.

8. The method of claim 1 wherein adjusting the electronic stability program includes:

providing an original ESP threshold of the electronic stability program; and

adjusting the original ESP threshold to define a new ESP threshold.

9. The method of claim 6 wherein adjusting the electronic stability program includes increasing the predetermined active band angle to increase a steering wheel angle range within which the vehicle is manually controlled.

10. The method of claim 7 wherein adjusting the electronic stability program includes increasing the maximum steering wheel angle and decreasing the minimum steering wheel angle to allow an increased rate of rotation range of the vehicle being manually controlled.

11. The method of claim 1 wherein adjusting the electronic stability program includes delaying the step of determining whether the vehicle is manually controllable in the sliding condition for a time period.

12. The method of claim 11 wherein the time period is between about 50-100 milliseconds.

13. The method of claim 8 wherein activating the stability control system to control the vehicle includes:

sensing a vehicle yaw rate of the vehicle;

calculating a yaw error based on the vehicle yaw rate and a model yaw rate;

comparing the yaw error to the new ESP threshold; and

determining the compensated brake pressure to be applied on the vehicle, the compensated brake pressure being based on the comparison of the yaw error and the new ESP threshold.

14. The method of claim 13 wherein determining the compensated brake pressure includes:

determining whether the yaw error is greater than the new ESP threshold;

finding a difference between the yaw error and the new ESP threshold, if the yaw error is greater than the new ESP threshold; and

multiplying the difference with a compensating proportional gain, the compensating proportional gain being based on time and yaw error.

15. The method of claim 2 wherein the minimum rate of change of the side slip angle is about 2°

-8°

.

16. The method of claim 2 wherein the minimum yaw rate error is between about 5°

to 15°

per second.

17. The method of claim 4 wherein the maximum rate of change of the side slip angle is about 10°

to 20°

.

18. The method of claim 4 wherein the maximum yaw rate error is about 35°

to 45°

per second.

19. The method of claim 6 wherein the predetermined active band is about 2°

to 5°

per second.

20. The method of claim 7 wherein the maximum steering wheel angle is about 90°

to 180°

.

21. The method of claim 7 wherein the minimum steering wheel angle is about 45°

to 60°

.

22. The method of claim 8 wherein the original ESP threshold is about 4°

to 6°

.

23. The method of claim 8 wherein the new ESP threshold is about between 10°

to 20°

.

24. The method of claim 13 wherein the model yaw rate is about 5°

to 45°

per second.

25. A method of regulating manual control for a compensating driver of a vehicle during a sliding condition of the vehicle having an electronic stability program using a stability control system, the method comprising:

recognizing the vehicle in a sliding condition;

determining whether the vehicle is manually controllable in the sliding condition;

adjusting an original ESP threshold to define a new ESP threshold configured within the electronic stability program, if the vehicle is determined to be manually controllable,

calculating a yaw error based on a vehicle yaw rate minus a model yaw rate, when the vehicle is not manually controllable;

comparing the yaw error to the new ESP threshold;

determining a compensated brake pressure to be applied on the vehicle, the compensated brake pressure being based on the comparison of the yaw error and the new ESP threshold; and

applying the compensated brake pressure on the vehicle.

26. The method of claim 25 wherein recognizing the vehicle in the sliding condition includes:

sensing a vehicle side slip angle of the vehicle;

determining a rate of change of the vehicle side slip angle;

comparing the rate of change of the side slip angle to a minimum rate of change of the side slip angle;

sensing a vehicle yaw rate of the vehicle;

comparing the vehicle yaw rate to a minimum yaw rate; and

determining that the vehicle is in the sliding condition, if the rate of change of the vehicle side slip angle is greater than the minimum rate of change of the side slip angle and the yaw rate error is greater than the minimum yaw rate error.

27. The method of claim 25 wherein determining whether the vehicle is manually controllable includes:

determining whether the vehicle is within a controllable range;

determining whether the vehicle is being steered toward a path on which the vehicle is sliding;

determining whether the vehicle is being steered at a rate which the vehicle is sliding;

determining whether a rate of rotation of the vehicle in the sliding condition is within a predetermined range; and

recognizing that the vehicle is manually controllable, if the vehicle is within the controllable range, if the vehicle is being steered toward the path on which the vehicle is sliding, if the vehicle is being steered within the rate at which the vehicle is sliding, and if the rate of rotation of the vehicle in the sliding condition is within the predetermined range.

28. The method of claim 27 wherein determining whether the vehicle is within the controllable range, the controllable range includes:

sensing a rate of change of a vehicle side slip angle of the vehicle;

comparing the rate of change of the vehicle side slip angle to a maximum rate of change of the side slip angle;

sensing a vehicle yaw rate of the vehicle;

determining a yaw rate error based on the vehicle yaw rate;

comparing the vehicle yaw rate error to a maximum yaw rate error of the vehicle; and

recognizing that the vehicle is within the controllable range, if the rate of change of the vehicle side slip angle is less than a maximum rate of change of the side slip angle and the vehicle yaw rate error is less than the maximum yaw rate error.

29. The method of claim 27 wherein determining whether the vehicle is being steered toward the path on which the vehicle is sliding includes sensing a steering wheel angle of the vehicle;

determining a rate of change of the steering wheel angle;

sensing a vehicle side slip angle;

determining a rate of change of the vehicle side slip angle;

comparing the rate of change of the steering wheel angle to the rate of change of the vehicle side slip angle; and

recognizing that the vehicle is being steered toward the path on which the vehicle is sliding, if the rate of change of the steering wheel angle is about the same as the rate of change of the vehicle side slip angle.

30. The method of claim 27 wherein determining whether the vehicle is being steered at the rate at which the vehicle is sliding includes:

sensing a vehicle side slip angle of the vehicle;

determining a rate of change of the vehicle side slip angle;

sensing a vehicle steering wheel angle of the vehicle;

determining a rate of change of the steering wheel angle;

comparing the rate of change of the steering wheel angle to the rate of change of the vehicle side slip angle and a predetermined active band angle; and

recognizing that the vehicle is being steered within the rate at which the vehicle is sliding, if;

the rate of change of the steering wheel angle is greater than the rate of change of the vehicle side slip angle minus the predetermined active band angle; and

the rate of change of the steering wheel is less than the rate of change of the vehicle side slip angle plus the predetermined active band angle, defining a steering wheel angle range within which the vehicle is manually steered.

31. The method of claim 27 wherein determining whether the rate of rotation of the vehicle in the sliding condition is within the predetermined range includes:

sensing a vehicle steering wheel angle of the vehicle;

comparing the vehicle steering wheel angle with a maximum steering wheel angle;

comparing the vehicle steering wheel angle with a minimum steering wheel angle; and

recognizing that the rate of rotation of the vehicle in the sliding condition is within the predetermined range, if;

the vehicle steering wheel angle is less than the maximum steering wheel angle; and

the vehicle steering wheel angle is greater than the minimum steering wheel angle, defining a rate of rotation range of the vehicle being manually controlled.

32. The method of claim 30 wherein adjusting the electronic stability program includes increasing the predetermined active band angle to increase a steering wheel angle range within which the vehicle is manually controlled.

33. The method of claim 31 wherein adjusting the electronic stability program includes increasing the maximum steering wheel angle and decreasing the minimum steering wheel angle to allow an increased rate of rotation range of the vehicle being manually controlled.

34. The method of claim 25 wherein adjusting the electronic stability program includes delaying the step of determining whether the vehicle is manually controllable in the sliding condition for a time period.

35. The method of claim 34 wherein the time period is about 50-100 milliseconds.

36. The method of claim 25 wherein determining the compensated brake pressure includes:

determining whether the yaw error is greater than the new ESP threshold;

finding a difference between the yaw error and the new ESP threshold, if the yaw error is greater than the new ESP threshold; and

multiplying the difference with a compensating proportional gain, the compensating proportional gain being based on time and yaw error.

37. The method of claim 26 wherein the minimum rate of change of the side slip angle is about 2°

to 8°

.

38. The method of claim 28 wherein the minimum yaw rate error is about 5°

to 15°

per second.

39. The method of claim 28 wherein the maximum rate of change of the side slip angle is about 10°

to 20°

.

40. The method of claim 28 wherein the maximum yaw rate error is about 35°

to 45°

per second.

41. The method of claim 30 wherein the predetermined active band is about 2°

to 5°

per second.

42. The method of claim 31 wherein the maximum steering wheel angle is about 90°

to 180°

.

43. The method of claim 31 wherein the minimum steering wheel angle is about 45°

to 60°

.

44. The method of claim 25 wherein the original ESP threshold is about 4°

to 6°

.

45. The method of claim 32 wherein the new ESP threshold is about between 10°

to 20°

.

46. A method of allowing manual control for a compensating driver of a vehicle during a sliding condition of the vehicle having an electronic stability program using a stability control system, the method comprising:

recognizing the vehicle in a sliding condition;

determining whether the vehicle is within a controllable range;

determining whether the vehicle is being steered toward a path on which the vehicle is sliding;

determining whether the vehicle is being steered at a rate which the vehicle is sliding;

determining whether a rate of rotation of the vehicle in the sliding condition is within a predetermined range;

recognizing that the vehicle is manually controllable, if;

the vehicle is within the controllable range, the vehicle is being steered toward the path on which the vehicle is sliding, the vehicle is being steered within the rate at which the vehicle is sliding, and the rate of rotation of the vehicle in the sliding condition is within the predetermined range;

adjusting the electronic stability program, if the vehicle is determined to be manually controllable;

activating the stability control system to control the vehicle, when the vehicle is not manually controllable; and

applying a compensated brake pressure based on the activation of the stability control system.

47. An electronic stability program system of the type having a stability control system, for allowing manual control of a vehicle during a sliding condition of the vehicle, the system comprising:

a mechanism for recognizing the vehicle in a sliding condition;

a mechanism for determining whether the vehicle is manually controllable in the sliding condition;

a mechanism for adjusting the electronic stability program and preventing the operation of the stability control system, if the vehicle is determined to be manually controllable;

a mechanism for activating the stability control system to control the vehicle, when the vehicle is not manually controllable; and

a mechanism for applying a compensated brake pressure based on the activation of the stability control system.