Vehicle acceleration based throttle area compensation

• US 6,304,806 B1
• Filed: 03/06/2000
• Issued: 10/16/2001
• Est. Priority Date: 03/06/2000
• Status: Expired due to Term

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Inventors: Stockbridge, John N., Bauerle, Paul A., Colby, Stephen E.
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Hernandez, Olga
• Application Number:
  US09/518,962
• Time in Patent Office: 589 Days
• Field of Search: 701/70, 701/110, 701/79, 701/78, 701/85, 701/93, 701/94
• US Class Current: 701/70
• CPC Class Codes: B60W 2050/0012 Feedforward or open loop systems
• CPC Class Codes: B60W 2050/0052 Filtering, filters
• CPC Class Codes: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2510/0671 Engine manifold pressure
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2720/106 Longitudinal acceleration
• 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

Abstract

A control system for maintaining powertrain responsiveness adjusts a throttle progression curve to compensate for different vehicle loads. The control system calculates an actual vehicle acceleration rate based on measured vehicle speed for evaluation of total mass being propelled by the vehicle. The calculated actual vehicle acceleration rate is compared to a target vehicle acceleration rate. A throttle progression curve is adjusted based on the results of the comparison so that a subsequent actual vehicle acceleration rate is closer to the target vehicle acceleration rate.

Claims

1. A control method for maintaining power train responsiveness to compensate for different vehicle loads comprising the steps of:

calculating an actual vehicle acceleration rate based on measured vehicle speed for evaluation of total vehicle weight and load being propelled by a vehicle;

looking up a target vehicle acceleration rate in a table based on delayed gear box torque and vehicle speed;

comparing a calculated actual vehicle acceleration rate to the target vehicle acceleration rate; and

adjusting a throttle progression curve based on results of the comparing step so that a subsequent actual vehicle acceleration rate is closer to the target vehicle acceleration rate.

2. The control method of claim 1 further comprising the step of:

compensating for altitude in the target vehicle acceleration by using gear box torque to reflect changes in barometric pressure.

3. The control method of claim 1 further comprising the step of:

looking up a throttle adjustment factor in a table based on the target vehicle acceleration rate and the actual vehicle acceleration rate.

4. The control method of claim 1 further comprising the step of:

preventing application of a revised throttle adjustment factor when engine vacuum is greater than a predetermined vacuum value.

5. The control method of claim 1 further comprising the step of:

storing the target vehicle acceleration in non-volatile memory between ignition cycles.

6. A control method for maintaining power train responsiveness to compensate for different vehicle loads comprising the steps of:

calculating an actual vehicle acceleration rate based on measured vehicle speed for evaluation of total vehicle weight and load being propelled by a vehicle;

comparing a calculated actual vehicle acceleration rate to a target vehicle acceleration rate;

adjusting a throttle progression curve based on results of the comparing step so that a subsequent actual vehicle acceleration rate is closer to the target vehicle acceleration rate; and

determining a throttle adjustment factor based on a ratio of target vehicle acceleration rate to actual vehicle acceleration rate.

7. The control method of claim 6 further comprising the step of:

prior to performing the determining step, averaging a ratio of target vehicle acceleration rate to actual vehicle acceleration rate over a predetermined period of time to reduce noise and driver induced fluctuations.

8. The control method of claim 6 further comprising the step of:

filtering the throttle adjustment factor with a predetermined maximum throttle adjustment value to prevent drastic changes in power train acceleration.

9. The control method of claim 6 further comprising the step of:

ramping the throttle adjustment factor in from zero vehicle speed to prevent drastic changes in vehicle response if a load has been removed from the vehicle.

10. The control method of claim 6 further comprising the step of:

if a current vehicle acceleration ratio is less than the target vehicle acceleration ratio, adjusting the throttle adjustment factor downward at a first predetermined rate.

11. The control method of claim 10 further comprising the step of:

if the current vehicle acceleration ratio is greater than the target vehicle acceleration ratio, adjusting the throttle adjustment factor upward at a second predetermined rate less than the first predetermined rate.

12. A control method for maintaining power train responsiveness to compensate for different vehicle loads comprising the steps of:

calculating an actual vehicle acceleration rate based on measured vehicle speed for evaluation of total vehicle weight and load being propelled by a vehicle;

comparing a calculated actual vehicle acceleration rate to a target vehicle acceleration rate;

adjusting a throttle progression curve based on results of the comparing step so that a subsequent actual vehicle acceleration rate is closer to the target vehicle acceleration rate; and

applying a throttle adjustment factor to the throttle progression curve in a manner to minimize perceivable changes in the throttle adjustment factor.

13. The control method or claim 12 further comprising the step of:

applying the throttle adjustment factor when an acceleration pedal position is less than a predetermined low value.

14. The control method of claim 12 further comprising the step of:

applying the throttle adjustment factor when an acceleration pedal position is greater than a predetermined high value.

15. The control method of claim 12 further comprising the step of:

applying the throttle adjustment factor when engine vacuum is less than a predetermined vacuum value.

16. The control method of claim 15 further comprising the step of:

determining the predetermined vacuum value from a lookup table based on revolutions per minute of the engine.

17. A control method for maintaining power train responsiveness to compensate for different vehicle loads comprising the steps of:

calculating an actual vehicle acceleration rate based on measured vehicle speed for evaluation of total vehicle weight and load being propelled by a vehicle;

comparing a calculated actual vehicle acceleration rate to a target vehicle acceleration rate;

adjusting a throttle progression curve based on results of the comparing step so that a subsequent actual vehicle acceleration rate is closer to the target vehicle acceleration rate; and

preventing application of a revised throttle adjustment factor when an acceleration pedal position is between a predetermined low value and a predetermined high value.

18. A control system for maintaining power train responsiveness to compensate for different vehicle loads comprising:

means for calculating an actual vehicle acceleration rate based on measured vehicle speed for evaluation of total vehicle weight and load being propelled by a vehicle;

means for looking up a target vehicle acceleration rate in a table based on delayed gear box torque and vehicle speed;

means for comparing a calculated actual vehicle acceleration rate to the target vehicle acceleration rate; and

means for adjusting a throttle progression curve based on results of the comparing step so that a subsequent actual vehicle acceleration rate is closer to the target vehicle acceleration rate.

19. The control system of claim 18 further comprising:

central processing means for receiving an input signal and for generating an output signal in accordance with a control program stored in memory.

20. The control system of claim 18 further comprising:

means for compensating for altitude in the target vehicle acceleration by using gear box torque to reflect changes in barometric pressure.

21. The control system of claim 18 further comprising:

means for looking up a throttle adjustment factor in a table based on the target vehicle acceleration rate and the actual vehicle acceleration rate.

22. The control system of claim 18 further comprising:

means for applying a throttle adjustment factor to the throttle progression curve in a manner to minimize perceivable changes in the throttle adjustment factor.

23. The control system of claim 18 further comprising:

means for preventing application of a revised throttle adjustment factor when an acceleration pedal position is between a predetermined low value and a predetermined high value.

24. The control system of claim 18 further comprising:

means for preventing application of a revised throttle adjustment factor when engine vacuum is greater than a predetermined vacuum value.

25. The control system of claim 18 further comprising:

means for storing the target vehicle acceleration in non-volatile memory between ignition cycles.

26. A control system for maintaining power train responsiveness to compensate for different vehicle loads comprising:

means for calculating an actual vehicle acceleration rate based on measured vehicle speed for evaluation of total vehicle weight and load being propelled by a vehicle;

means for comparing a calculated actual vehicle acceleration rate to a target vehicle acceleration rate;

means for adjusting a throttle progression curve based on results of the comparing step so that a subsequent actual vehicle acceleration rate is closer to the target vehicle acceleration rate; and

means for determining a throttle adjustment factor based on a ratio of target vehicle acceleration rate to actual vehicle acceleration rate.

27. The control system of claim 26 further comprising:

prior to determining the throttle adjustment factor with the determining means, means for averaging a ratio of target vehicle acceleration rate to actual vehicle acceleration rate over a predetermined period of time to reduce noise and driver induced fluctuations.

28. The control system of claim 26 further comprising:

means for filtering the throttle adjustment factor with a predetermined maximum throttle adjustment value to prevent drastic changes in power train acceleration.

29. The control system of claim 26 further comprising:

means for ramping the throttle adjustment factor in from zero vehicle speed to prevent drastic changes in vehicle response if a load has been removed from the vehicle.

30. The control system of claim 26 further comprising:

means for adjusting the throttle adjustment factor downward at a first predetermined rate, if a current vehicle acceleration ratio is less than the target vehicle acceleration ratio.

31. The control system of claim 30 further comprising:

means for adjusting the throttle adjustment factor upward at a second predetermined rate less than the first predetermined rate, if the current vehicle acceleration ratio is greater than the target vehicle acceleration ratio.

32. A control system for maintaining power train responsiveness to compensate for different vehicle loads comprising:

means for calculating an actual vehicle acceleration rate based on measured vehicle speed for evaluation of total vehicle weight and load being propelled by a vehicle;

means for comparing a calculated actual vehicle acceleration rate to a target vehicle acceleration rate;

means for adjusting a throttle progression curve based on results of the comparing step so that a subsequent actual vehicle acceleration rate is closer to the target vehicle acceleration rate; and

means for applying the throttle adjustment factor when an acceleration pedal position is less than a predetermined low value.

33. The control system of claim 32 further comprising:

means for applying the throttle adjustment factor when an acceleration pedal position is greater than a predetermined high value.

34. The control system of claim 32 further comprising:

means for applying the throttle adjustment factor when engine vacuum is less than a predetermined vacuum value.

35. The control system of claim 34 further comprising the step of:

determining the predetermined vacuum value from a lookup table based on revolutions per minute of the engine.