Method for Controlling Vehicle Launch

• US 20130002210A1
• Filed: 06/30/2011
• Published: 01/03/2013
• Est. Priority Date: 06/30/2011
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Gibson, Alex O'Connor, DeMarco, John Anthony, Grant, Robert Michael, Gale, Allan Roy
• Granted Patent: US 8,612,113 B2
• Time in Patent Office: Days
• US Class Current: 322/7
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/20 including control of steering systems
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/18 Steering angle
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 2710/083 Torque
• CPC Class Codes: B60W 2710/202 Steering torque
• CPC Class Codes: B60W 2710/305 target power to auxiliaries
• CPC Class Codes: B60W 30/18018 Start-stop drive, e.g. in a traffic jam
• CPC Class Codes: B60W 30/18027 Drive off, accelerating from standstill
• CPC Class Codes: B60W 30/1886 Controlling power supply to auxiliary devices
• CPC Class Codes: B60W 30/192 Mitigating problems related to power-up or power-down of the driveline, e.g. start-up of a cold engine
• CPC Class Codes: B62D 5/0481 monitoring the steering system, e.g. failures
• CPC Class Codes: H02P 9/008 wherein the generator is controlled by the requirements of the prime mover

Abstract

A method for improving starting of an engine that may be repeatedly stopped and started is presented. In one embodiment, the method adjusts a transmission actuator in response to engine combustion during an engine start. The method may improve vehicle launch for stop/start vehicles.

Claims

1. A vehicle launch control method, comprising:

adjusting a load of an alternator applied to an engine in response to a steering input and an engine torque request.

2. The method of claim 1, where the load of the alternator is adjusted in response to weightings of the steering input and the engine torque request.

3. The method of claim 1, where load of the alternator is adjusted during an engine start until a threshold vehicle condition is exceeded.

4. The method of claim 3, where the threshold vehicle condition is at least one of a vehicle speed, engine speed, vehicle acceleration rate, and engine acceleration rate.

5. The method of claim 1, where the load of the alternator is adjusted via adjusting a field current of the alternator.

6. The method of claim 1, where the load of the alternator applied to the engine during engine cranking is limited via supplying substantially zero current to the alternator.

7. The method of claim 1, further comprising decreasing a torque supplied to vehicle wheels in response to an increased steering angle request.

8. The method of claim 1, further comprising increasing the load of the alternator applied to the engine in response to an increased steering angle request.

9. A vehicle launch control method, comprising:

in a first mode where an operator input is less than a threshold,

adjusting an alternator load applied to an engine to control engine speed and limit a voltage drop caused by an electric power steering system;

in a second mode where the operator input is greater than the threshold,

adjusting the alternator load applied to the engine responsive to the operator accelerator input and a steering input.

10. The method of claim 9, where the operator input is an accelerator command.

11. The method of claim 9, where the first and second mode are entered after engine cranking and before a threshold vehicle condition is met.

12. A method of claim 9, where the threshold vehicle condition is one of a vehicle speed, vehicle acceleration, engine speed, and engine acceleration.

13. The method of claim 11, where during engine cranking current supplied to an electric steering system is limited.

14. The method of claim 9, where alternator loading of the engine is allowed to commence in response to a combustion event.

15. A system for controlling vehicle launch, comprising:

an alternator;

a starter;

an engine; and

a controller, the controller including instructions to automatically start the engine in absence of a dedicated operator engine start request, the controller including additional instructions to adjust an alternator load applied to the engine in response to an engine torque request and a steering request, the controller including additional instructions to adjust alternator load applied to the engine in response to vehicle wheel slip.

16. The system of claim 15, where the alternator load applied to the engine in response to vehicle wheel slip is increased.

17. The system of claim 15, further comprising additional controller instructions to adjust alternator load supplied to the engine in response to an engine torque reserve.

18. The system of claim 15, further comprising additional controller instructions for adjusting the alternator load applied to the engine in response to a predicted combustion event of the engine.

19. The system of claim 15, further comprising an electric steering system.

20. The system of claim 19, where the electric steering system is electrically coupled to a battery and the alternator.

21. A vehicle launch control method, comprising:

automatically restarting an engine of the vehicle from a stopped vehicle condition;

during higher steering operation conditions, diverting a greater amount of engine output away from forward progress wheel torque generation and to a power steering system; and

during lower steering operation conditions, diverting a lesser amount of engine output away from forward progress wheel torque generation and to the power steering system.

22. The method of claim 21, where higher steering operating conditions include steering torque request greater than a threshold, steering torque output greater than a threshold, steering angle greater than a threshold.

23. The method of claim 21, where the diverting occurs during an engine start before engine speed reaches a threshold and before engine torque reaches a threshold.

24. The method of claim 23, where the diverting begins during an engine start after a starter is disengaged.