Traction control system and method for a vehicle

• US 7,499,787 B2
• Filed: 10/07/2004
• Issued: 03/03/2009
• Est. Priority Date: 10/07/2004
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Fodor, Michael, Hrovat, Davor, McConnell, Mitch
• Primary Examiner(s): Nguyen; Cuong H
• Application Number:
  US10/961,452
• Publication Number:
  US 20060080022A1
• Time in Patent Office: 1,608 Days
• Field of Search: 701/82, 701/205, 701/54, 701/91, 701/87, 701/80, 701/84, 701/215, 477/115, 477/107, 180/197, 180/244, 361/238, 303/112, 303/113.2
• US Class Current: 701/82
• CPC Class Codes: B60K 28/16 responsive to, or preventing, skidding of wheels brake control systems for vehicle drive stability B60T8/1755; arrangements responsive to a speed condition for adjusting wheel braking force B60T8/32; control of vehicle driving stability otherwise than by controlling the propulsion unit only B60W30/02; preventing wheel slippage by reducing power in rail vehicles B61C15/00
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2552/40 Coefficient of friction
• CPC Class Codes: B60W 2710/0605 Throttle position
• CPC Class Codes: F02D 11/105 characterised by the function converting demand to actuation, e.g. a map indicating relations between an accelerator pedal position and throttle valve opening or target engine torque
• CPC Class Codes: F02D 2250/18 Control of the engine output torque
• CPC Class Codes: F02D 41/021 Introducing corrections for particular conditions exterior to the engine conjoint control of vehicle sub-units for propelling the vehicle B60W30/18

Abstract

In one example, A method for controlling a powertrain of a vehicle with wheels, the vehicle having a pedal actuated by a driver, is described. The method may include generating powertrain torque transmitted to the wheels in a first relation to actuation of the pedal by the driver during a first condition where said transmitted torque causes said wheels to slip relative to a surface; overriding said driver actuated powertrain torque to control said slip; and during a second condition after said first condition where said vehicle is moving less than a threshold, generating powertrain torque transmitted to the wheels in a second relation to actuation of the pedal by the driver, where for a given pedal position, less powertrain torque is transmitted with said second relation compared to said first relation.

Claims

1. A method for controlling a powertrain of a vehicle with wheels, the vehicle having a pedal actuated by a driver, the method comprising:

generating powertrain torque transmitted to the wheels in a first relation to actuation of the pedal by the driver during a first condition where said transmitted torque causes said wheels to slip relative to a surface;

overriding said driver actuated powertrain torque to control said slip; and

during a second condition after said first condition where said vehicle is moving less than a threshold, generating powertrain torque transmitted to the wheels in a second relation to actuation of the pedal by the driver and via direct control by the driver actuated powertrain torque, without active slip control, where for a given pedal position, less powertrain torque is transmitted with said second relation compared to said first relation.

2. The method of claim 1 wherein said second condition includes said vehicle substantially in a non-moving condition.

3. The method of claim 2 wherein said second condition includes said vehicle substantially in said non-moving condition for a duration.

4. The method of claim 1 wherein said second condition is in response to said slip.

5. The method of claim 1 wherein said second condition is in response to a release of said pedal.

6. The method of claim 1 wherein said second relation is based on said first relation and an estimated friction amount during said slip.

7. The method of claim 1 wherein said second relation is set to provide substantially a maximum possible torque that may be transmitted for current road conditions at substantially full pedal engagement.

8. The method of claim 1 wherein during said first condition, powertrain torque is reduced based on said slip.

9. The method of claim 1 wherein said second condition is in response to actuation of a brake pedal.

16. The method of claim 1, wherein after the second condition when the vehicle is moving a sufficient amount, powertrain torque transmitted to the wheels is gradually transitioned to be generated in said first relation to actuation of the pedal by the driver.

10. A method for controlling a powertrain of a vehicle with wheels, the vehicle having a pedal actuated by a driver, the method comprising:

generating powertrain torque transmitted to the wheels in a first relation to actuation of the pedal by the driver during a first condition where said transmitted torque causes said wheels to slip relative to a surface;

overriding said driver actuated powertrain torque to control and reduce said slip; and

during a second condition after said first condition where said vehicle is moving less than a threshold and the driver has released the pedal, generating powertrain torque transmitted to the wheels in a second relation to actuation of the pedal by the driver via direct control by the driver actuated powertrain torque, without active slip control, where for a given pedal position, less powertrain torque is transmitted with said second relation compared to said first relation.

11. The method of claim 10 wherein said second condition includes said vehicle substantially in a non-moving condition.

12. The method of claim 11 wherein said second condition includes said vehicle substantially in said non-moving condition for a time duration.

13. The method of claim 10 wherein said second relation is based on said first relation and an estimated friction amount during said slip, and said second relation is set to provide substantially a maximum possible torque that may be transmitted for current road conditions at substantially full pedal engagement.

14. The method of claim 10 wherein during said first condition, powertrain torque is reduced based on said slip via reduction in engine torque by at least one of reducing a throttle plate angle and retarding ignition timing.

15. The method of claim 10 wherein said second condition is in response to actuation of a brake pedal.