Driving force control apparatus and driving force control method

• US 8,075,445 B2
• Filed: 07/24/2006
• Issued: 12/13/2011
• Est. Priority Date: 08/03/2005
• Status: Expired due to Fees

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Shiiba, Kazuyuki, Iwatsuki, Kunihiro, Iizuka, Shinya
• Primary Examiner(s): Le, David D
• Assistant Examiner(s): KNIGHT, DEREK DOUGLAS
• Application Number:
  US11/491,039
• Publication Number:
  US 20070032341A1
• Time in Patent Office: 1,968 Days
• Field of Search: 701/65, 477/97
• US Class Current: 477/97
• CPC Class Codes: F16H 2059/666 Determining road conditions by using vehicle location or position, e.g. from global navigation systems [GPS]
• CPC Class Codes: F16H 2061/0234 Adapting the ratios to special vehicle conditions
• CPC Class Codes: F16H 59/54 dependent on signals from the brakes, e.g. parking brakes
• CPC Class Codes: F16H 59/66 Road conditions, e.g. slope, slippery
• CPC Class Codes: F16H 61/0213 characterised by the method for generating shift signals
• CPC Class Codes: F16H 61/21 Providing engine brake control

Abstract

In a driving force control apparatus and a driving force control method, a curve ahead of a vehicle is detected; a target vehicle speed is set to pass the curve; a starting-point shift speed is set to pass the starting point of the curve; and an end-point shift speed is set to pass the end point of the curve. After a shift speed is changed to the starting-point shift speed, it is determined whether an additional engine brake is required at the starting-point shift speed. If it is determined that the engine brake is not required, the shift speed is changed to the end-point shift speed. Alternatively, if a vehicle speed is lower than or equal to a value corresponding to the target vehicle speed after the shift speed is changed to the starting-point shift speed, the shift speed is changed to the end-point shift speed.

Claims

1. A driving force control apparatus, comprising:

a controller that

detects a curve ahead of a vehicle,

sets a target vehicle speed to pass the detected curve,

sets a starting-point shift speed based on the detected curve ahead of the vehicle, to pass a starting point of the detected curve, and

sets an end-point shift speed different from the starting-point shift speed to pass an end point of the detected curve different from the starting point of the detected curve,

wherein the controller changes a shift speed to the end-point shift speed if, after the controller changes a shift speed to the starting-point shift speed, a vehicle speed is lower than or equal to a value corresponding to the target vehicle speed and a braking member is operated.

2. The driving force control apparatus according to claim 1, wherein the controller determines whether an additional engine brake is required at the starting-point shift speed, based on whether an accelerator member is operated.

3. The driving force control apparatus according to claim 1, wherein the controller changes the shift speed to the end-point shift speed if a parameter indicating a deceleration state of the vehicle is larger than or equal to a predetermined value when the braking member is operated.

4. The driving force control apparatus according to claim 3, wherein the parameter indicating the deceleration state of the vehicle is any one of a brake master cylinder pressure, an acceleration of the vehicle, a rate of change in the acceleration of the vehicle, a brake pedal stroke, and a brake pedal force.

5. The driving force control apparatus according to claim 1, wherein the value corresponding to the target vehicle speed is a sum of a target turning vehicle speed determined based on a curvature radius of the curve and a target lateral acceleration, and a correction amount that is changed based on the curvature radius of the curve.

6. The driving force control apparatus according to claim 5, wherein the correction amount decreases as the curvature radius of the curve decreases.

7. The driving force control apparatus according to claim 1, wherein the controller does not change the shift speed to the end-point shift speed if, after the controller changes the shift speed to the starting-point shift speed, the vehicle speed is not lower than or equal to the value corresponding to the target vehicle speed or the braking member is not operated.

8. The driving force control apparatus according to claim 1 wherein the controller changes the shift speed to the end-point shift speed if a parameter indicating a deceleration state of the vehicle is larger than or equal to a predetermined value when the braking member is operated.

9. The driving force control apparatus according to claim 8, wherein the parameter indicating the deceleration state of the vehicle is any one of a brake master cylinder pressure, an acceleration of the vehicle, a rate of change in the acceleration of the vehicle, a brake pedal stroke, and a brake pedal force.

10. The driving force control apparatus according to claim 1, wherein the value corresponding to the target vehicle speed is a sum of a target turning vehicle speed determined based on a curvature radius of the curve and a target lateral acceleration, and a correction amount that is changed based on the curvature radius of the curve.

11. The driving force control apparatus according to claim 10, wherein the correction amount decreases as the curvature radius of the curve decreases.

12. The driving force control apparatus according to claim 1, wherein the end-point shift speed is set based on the detected curve ahead of the vehicle.

13. The driving force control apparatus according to claim 12, wherein

the end-point shift speed is set based on a curvature radius and road gradient of the curve.

14. A driving force control method, comprising:

detecting a curve ahead of a vehicle;

setting a target vehicle speed to pass the detected curve;

setting a starting-point shift speed based on the detected curve ahead of the vehicle, to pass a starting point of the detected curve;

setting an end-point shift speed different from the starting-point shift speed to pass an end point of the detected curve different from the starting point of the detected curve; and

changing a shift speed to the end-point shift speed if, after a shift speed is changed to the starting-point shift speed, a vehicle speed is lower than or equal to a value corresponding to the target vehicle speed and a braking member is operated.

15. The driving force control method according to claim 14, wherein it is determined whether an additional engine brake is required at the starting-point shift speed, based on whether an accelerator member is operated.

16. The driving force control method according to claim 14, wherein the shift speed is changed to the end-point shift speed if a parameter indicating a deceleration state of the vehicle is larger than or equal to a predetermined value when the braking member is operated.

17. The driving force control apparatus according to claim 16, wherein the parameter indicating the deceleration state of the vehicle is any one of a brake master cylinder pressure, an acceleration of the vehicle, a rate of change in the acceleration of the vehicle, a brake pedal stroke, and a brake pedal force.

18. The driving force control apparatus according to claim 14, wherein the value corresponding to the target vehicle speed is a sum of a target turning vehicle speed determined based on a curvature radius of the curve and a target lateral acceleration, and a correction amount that is changed based on the curvature radius of the curve.

19. The driving force control apparatus according to claim 18, wherein the correction amount decreases as the curvature radius of the curve decreases.

20. The driving force control method according to claim 14, wherein

the shift speed is not changed to the end-point shift speed if, after the shift speed is changed to the starting-point shift speed, the vehicle speed is not lower than or equal to the value corresponding to the target vehicle speed or the braking member is not operated.

21. The driving force control method according to claim 14, wherein

the shift speed is changed to the end-point shift speed if a parameter indicating a deceleration state of the vehicle is larger than or equal to a predetermined value when the braking member is operated.

22. The driving force control method according to claim 21, wherein the parameter indicating the deceleration state of the vehicle is any one of a brake master cylinder pressure, an acceleration of the vehicle, a rate of change in the acceleration of the vehicle, a brake pedal stroke, and a brake pedal force.

23. The driving force control method according to claim 14, wherein the value corresponding to the target vehicle speed is a sum of a target turning vehicle speed determined based on a curvature radius of the curve and a target lateral acceleration, and a correction amount that is changed based on the curvature radius of the curve.

24. The driving force control method according to claim 23, wherein the correction amount decreases as the curvature radius of the curve decreases.

25. The driving force control method according to claim 14, wherein

the end-point shift speed is set based on the detected curve ahead of the vehicle.

26. The driving force control method according to claim 25, wherein

the end-point shift speed is set based on a curvature radius and road gradient of the curve.