Deceleration control apparatus and method for a vehicle

• US 7,469,178 B2
• Filed: 11/30/2004
• Issued: 12/23/2008
• Est. Priority Date: 02/10/2004
• 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
• Primary Examiner(s): ARTHUR JEANGLAUDE, GERTRUDE
• Application Number:
  US10/998,562
• Publication Number:
  US 20050187694A1
• Time in Patent Office: 1,484 Days
• Field of Search: 701/65, 701/70, 701/79, 701/80, 701/87, 701/90, 701/96, 701/91, 303/152, 477/40, 340/903
• US Class Current: 701/70
• CPC Class Codes: B60T 2210/24 Curve radius
• CPC Class Codes: B60T 2260/04 Automatic transmission
• CPC Class Codes: B60W 10/115 with planetary gears
• CPC Class Codes: B60W 10/184 with wheel brakes
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2552/20 Road profile, i.e. the change in elevation or curvature of a plurality of continuous road segments
• CPC Class Codes: B60W 2552/30 Road curve radius
• CPC Class Codes: B60W 2720/106 Longitudinal acceleration
• CPC Class Codes: B60W 2720/125 Lateral acceleration
• CPC Class Codes: B60W 30/18109 Braking

Abstract

A deceleration control apparatus and method for a vehicle, which performs deceleration control on the vehicle by an operation of a brake system which applies a braking force to the vehicle and a shift operation which shifts a transmission of the vehicle into a relatively low speed or speed ratio, performs the shift operation and the operation of the brake system such that a target deceleration set based on a curvature or curvature radius of a curve in a road ahead of the vehicle, a distance to the curve, and a vehicle speed, acts on the vehicle. As a result, a desired deceleration according to the distance to the curve is able to be applied to the vehicle.

Claims

1. A deceleration control apparatus for a vehicle, which performs deceleration control on the vehicle by an operation of a brake system which applies a braking force to the vehicle and a shift operation which shifts a transmission of the vehicle into a relatively low speed or speed ratio, comprising:

a controller which i) determines a deceleration to be applied to the vehicle as a base deceleration based on a curvature or curvature radius of a curve in a road ahead of the vehicle, and ii) determines a deceleration correction amount based on a distance to the curve, and wherein the deceleration correction amount is combined with the base deceleration to control deceleration of the vehicle.

2. The deceleration control apparatus for a vehicle according to claim 1, wherein the controller determines the base deceleration as a speed change amount in the shift operation.

3. The deceleration control apparatus for a vehicle according to claim 1, wherein the correction amount is a deceleration to be applied to the vehicle by the operation of the braking system.

4. The deceleration control apparatus for a vehicle according to claim 1, wherein the correction amount includes zero.

5. The deceleration control apparatus for a vehicle according to claim 1, wherein the correction amount is determined based on the curvature or curvature radius of the curve, the vehicle speed, and a target lateral acceleration at the curve, in addition to the distance to the curve.

6. The deceleration control apparatus for a vehicle according to claim 1, wherein the controller controls the brake system so that deceleration produced by the brake system gradually decreases from the time the shift operation ends.

7. The deceleration control apparatus for a vehicle according to claim 1, wherein the controller determines the correction amount of the deceleration based on vehicle speed.

8. The deceleration control apparatus according to claim 1, wherein, based on current vehicle speed and the distance to the curve, the controller determines whether deceleration control is needed, and if the controller determines deceleration control is needed, the controller controls deceleration using said base deceleration combined with said deceleration correction amount.

9. The deceleration control apparatus according to claim 8, wherein, if the controller determines deceleration control is needed, the controller controls deceleration using said base deceleration and said deceleration correction amount even if the vehicle has not yet begun to turn to travel in the curve.

10. The deceleration control according to claim 9, wherein if the controller determines deceleration control is needed the controller controls deceleration using said base deceleration and said deceleration correction amount even if the vehicle is traveling straight.

11. The deceleration control according to claim 1, wherein the controller determines that a deceleration control is needed in response to a determination that:

(a) an accelerator is off, and (b) braking is insufficient to reach a predetermined vehicle speed at a predetermined position of the curve; and

wherein, in response to a determination that deceleration control is needed, the controller controls deceleration using the base deceleration and the deceleration correction amount.

12. The deceleration control according to claim 11, wherein the base deceleration is determined based on a radius of the curve and a gradient of the road, and wherein the deceleration correction amount is determined based on distance to the curve and vehicle speed.

13. The deceleration control according to claim 1, wherein the controller controls a shift operation based on the radius of the curve, and wherein the controller controls braking based on distance to the curve.

14. A deceleration control method for a vehicle, by which deceleration control is performed on the vehicle by an operation of a brake system which applies a braking force to the vehicle and a shift operation which shifts a transmission of the vehicle into a relatively low speed or speed ratio, comprising:

determining a deceleration to be applied to the vehicle as a base deceleration based on a curvature or curvature radius of a curve in a road ahead of the vehicle;

determining a deceleration correction amount based on a distance to the curve, and wherein the deceleration correction amount is combined with the base deceleration amount to control deceleration of the vehicle; and

performing the shift operation and the operation of the brake system such that a deceleration which is the sum of the base deceleration and the correction amount acts on the vehicle.

15. The deceleration control method for a vehicle according to claim 14, wherein the base deceleration is determined as a speed change amount in the shift operation.

16. The deceleration control method for a vehicle according to claim 14, wherein the correction amount is a deceleration to be applied to the vehicle by the operation of the braking system.

17. The deceleration control method for a vehicle according to claim 14, wherein the correction amount includes zero.

18. The deceleration control method for a vehicle according to claim 14, wherein the correction amount is determined based on the curvature or curvature radius of the curve, a vehicle speed, and a target lateral acceleration at the curve, in addition to the distance to the curve.

19. The deceleration control method for a vehicle according to claim 14, further comprising:

controlling the brake system so that deceleration produced by the brake system gradually decreases from the time the shift operation ends.

20. The deceleration control method for a vehicle according to claim 14, wherein the correction amount is based on vehicle speed.