Coordinated torque control security method and apparatus

• US 20060178797A1
• Filed: 02/09/2005
• Published: 08/10/2006
• Est. Priority Date: 02/09/2005
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Hartrey, Timothy J., Larsen, John F., Ender, Tom C., Dimarco, Gene
• Granted Patent: US 7,254,472 B2
• Time in Patent Office: Days
• US Class Current: 701/54
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 2510/105 Output torque
• CPC Class Codes: B60W 2530/20 Tyre data
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 30/188 Controlling power parameters of the driveline, e.g. determining the required power
• CPC Class Codes: B60W 40/1005 Driving resistance

Abstract

A method of preventing undesirable vehicle behavior in a vehicle torque control system that includes determining an expected axle torque based on a vehicle speed, a powerplant profile, an accelerator pedal position and/or a cruise control signal. The method also includes estimating an actual axle torque of a powerplant based on a powerplant maximum torque, a throttle position and powertrain inefficiencies and converting the expected axle torque to an expected acceleration and the actual axle torque to an actual acceleration based on a wheel radius and a road load. The method further includes regulating a torque output of a powerplant when a rate-of-change in a difference between the expected acceleration and the estimated actual acceleration is greater than a first threshold.

Claims

1. A method of preventing undesirable vehicle behavior in a vehicle torque control system comprising:

determining an expected axle torque based on a vehicle speed, a powerplant profile and one of an accelerator pedal position and a cruise control signal;

estimating an actual axle torque of a powerplant based on a powerplant maximum torque, an engine speed and engine system inefficiencies;

converting said expected axle torque to an expected acceleration based on a wheel radius and a road load;

converting said actual axle torque to an actual acceleration based on said wheel radius and said road load; and

regulating a torque output of a powerplant when a rate-of-change in a difference between said expected acceleration and said actual acceleration is greater than a first threshold.

2. The method of claim 1 further comprising comparing said actual axle torque to an idle range.

3. The method of claim 2 further comprising regulating said torque output when said actual axle torque is not within said idle range during a first time period after said vehicle control system detects an idle torque request.

4. The method of claim 3 further comprising detecting said idle torque request from one of said accelerator pedal position and a cruise control signal.

5. The method of claim 2 further comprising setting an idle range flag when said actual axle torque is within said idle range.

6. The method of claim 5 further comprising setting an idle torque request flag when the vehicle control system detects an idle torque request.

7. The method of claim 6 further comprising regulating said torque output when said idle range flag is not detected during a second time period after said vehicle control system detects said idle torque request flag is set.

8. The method of claim 1 wherein regulating said torque output includes one of setting a service code and reducing said torque output.

9. The method of claim 1 wherein determining said expected axle torque is further based on one of a driver history, a powerplant status and environmental factors.

10. A torque control system for a vehicle, comprising:

a powerplant that produces a torque output;

operator inputs including one of an accelerator pedal position and a cruise control signal; and

a control module that controls said powerplant, that determines an expected axle torque based on a vehicle speed, a powerplant profile and one of an accelerator position and a cruise control signal, that estimates an actual axle torque of a powerplant based on a powerplant maximum torque, an engine speed and engine system inefficiencies, that converts said expected axle torque to an expected acceleration based on a wheel radius and a road load, that converts said actual axle torque to an actual acceleration based on said wheel radius and said road load, and that regulates said torque output of said powerplant when a rate-of-change in the difference between said expected acceleration and said actual acceleration is greater than a first threshold.

11. The torque control system of claim 10 wherein said control module compares said actual axle torque to an idle range.

12. The torque control system of claim 11 wherein said control module regulates said torque output of said powerplant when said actual axle torque is not within said idle range during a first time period after said control module detects an idle torque request.

13. The torque control system of claim 12 wherein said control module detects said idle torque request from one of said accelerator pedal position and a cruise control signal.

14. The torque control system of claim 11 wherein said control module sets an idle range flag when said powerplant torque is within said idle range.

15. The torque control system of claim 14 wherein said control module sets an idle torque request flag when said control module detects an idle torque request.

16. The torque control system of claim 10 wherein said control module regulates said torque output when said idle range flag is not detected during said first time period after said idle torque request flag is set.

17. The torque control system of claim 10 wherein said control module regulates said torque output by one of setting a service code and reducing said torque output.

18. The torque control system of claim 10 wherein said control module further determines said expected axle torque based on one of a driver history, a powerplant status, environmental factors, a brake pedal position and a telematics system signal.

19. A method of preventing undesirable vehicle behavior in a vehicle torque control system comprising:

determining an expected axle torque based on a vehicle speed, a powerplant profile and one of an accelerator pedal position and a cruise control signal;

estimating an actual axle torque of a powerplant based on a powerplant maximum torque, an engine speed and engine system inefficiencies;

converting said expected axle torque to an expected acceleration based on a wheel radius and a road load;

converting said actual axle torque to an actual acceleration based on said wheel radius and said road load;

comparing said actual axle torque to an idle range; and

regulating a torque output of a powerplant when said actual axle torque is not within said idle range during a first time period after said vehicle torque control system detects an idle torque request.

20. The method of claim 19 further comprising detecting said idle torque request from one of said accelerator pedal position and a cruise control signal.

21. The method of claim 19 further comprising setting an idle range flag when said actual axle torque is within said idle range.

22. The method of claim 21 further comprising setting an idle torque request flag when the vehicle control system detects said idle torque request.

23. The method of claim 22 further comprising regulating said torque output when said idle range flag is not detected during said first time period said idle torque request flag is set.

24. The method of claim 19 wherein regulating said torque output includes one of setting a service code and reducing said torque output.

25. The method of claim 19 wherein determining an expected axle torque is further based on one of a driver history, a powerplant status and an environmental factors.

26. The method of claim 19 further comprising regulating said torque output when a rate-of-change in a difference between said expected acceleration and said actual acceleration is greater than a first threshold.

27. A torque control system for a vehicle, comprising:

a powerplant that produces a torque output;

operator inputs including one of an accelerator pedal position and a cruise control signal; and

a control module that controls said powerplant, that determines an expected axle torque based on a vehicle speed, a powerplant profile and one of an accelerator position and a cruise control signal, that estimates an actual axle torque of a powerplant based on a powerplant maximum torque, an engine speed and engine system inefficiencies, that converts said expected axle torque to an expected acceleration based on a wheel radius and a road load, that converts said actual torque to an actual acceleration based on said wheel radius and said road load, that compares if said actual axle torque to an idle range and that regulates said torque output when said actual axle torque is not within said idle range during a first time period after said control module detects an idle torque request.

28. The torque control system of claim 27 wherein said control module detects said idle torque request from one of said accelerator pedal position and a cruise control signal.

29. The torque control system of claim 27 wherein said control module sets an idle range flag when said powerplant torque is within said idle range.

30. The torque control system of claim 29 wherein said control module sets an idle torque request flag when said control module detects an idle torque request.

31. The torque control system of claim 27 wherein said control module regulates said torque output when said idle range flag is not detected during said first time period after said idle torque request flag is set.

32. The torque control system of claim 27 wherein said control module further regulates said powerplant torque if a rate-of-change in a difference between said expected acceleration and said actual acceleration is greater than a first threshold.

33. The torque control system of claim 27 wherein said control module further determines said expected axle torque based on a driver history, a powerplant status, environmental factors, a brake pedal position and a telematics system signal.

34. The torque control system of claim 32 wherein said control module regulates said powerplant torque by one of setting a service code and reducing torque output.