E-DRIVE TORQUE SENSING VEHICLE STATE ESTIMATION METHODS FOR VEHICLE CONTROL

• US 20150274159A1
• Filed: 03/25/2014
• Published: 10/01/2015
• Est. Priority Date: 03/25/2014
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Lu, Jianbo, Yu, Hai, Liang, Wei
• Granted Patent: US 9,296,391 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60T 2260/04 Automatic transmission
• CPC Class Codes: B60T 8/171 Detecting parameters used in the regulation; Measuring values used in the regulation
• CPC Class Codes: B60T 8/175 Brake regulation specially adapted to prevent excessive wheel spin during vehicle acceleration, e.g. for traction control safety devices for propulsion unit control responsive to, or preventing, skidding of wheels B60K28/16
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 2510/083 Torque
• CPC Class Codes: B60W 2510/105 Output torque
• CPC Class Codes: B60W 2510/182 Brake pressure, e.g. of fluid or between pad and disc
• CPC Class Codes: B60W 2520/30 Wheel torque
• CPC Class Codes: B60W 30/02 Control of vehicle driving stability
• CPC Class Codes: B60W 40/10 related to vehicle motion
• CPC Class Codes: B60W 40/12 related to parameters of the vehicle itself , e.g. tyre models
• CPC Class Codes: G01L 3/245 by measuring and simultaneously multiplying pressure and velocity
• CPC Class Codes: G01L 5/13 for measuring the tractive or propulsive power of vehicles
• CPC Class Codes: Y10S 903/93 Conjoint control of different elements

Abstract

Vehicle state estimation methods include measuring torque, using the measured torque to formulate a vehicle state estimation for vehicle control and applying the vehicle state estimation to control the vehicle.

Claims

1. A hybrid vehicle control method, comprising:

controlling the vehicle using a vehicle state estimation based on a measured torque.

2. The method of claim 1 further comprising measuring torque by measuring actuation torque.

3. The method of claim 2 wherein measuring actuation torque comprises transforming the measured torque to the individual wheel locations to estimate linear active wheel torque.

4. The method of claim 2 wherein measuring actuation torque comprises transforming the measured torque to the individual wheel locations to estimate nonlinear active wheel torque.

5. The method of claim 2 wherein measuring torque comprises measuring automatic transmission torque.

6. The method of claim 2 wherein measuring torque comprises measuring motor torque.

7. The method of claim 6 wherein measuring motor torque comprises measuring engine torque in hybrid mode of a hybrid vehicle.

8. The method of claim 2 wherein measuring torque comprises measuring wheel torque.

9. The method of claim 2 wherein measuring torque comprises measuring brake pressure and computing brake torque from the measured brake pressure.

10. A vehicle state estimation method, comprising:

measuring torque;

using the measured torque to formulate a vehicle state estimation for vehicle control, the vehicle state estimation including at least one of the following;

longitudinal accelerometer offset compensation estimation, vehicle loading estimation, brake effort estimation, brake balancing estimation, regenerative brake redistribution estimation, brake lining friction coefficient estimation, acceleration reconstruction estimation, and enhanced wheel slip control estimation; and

applying the vehicle state estimation to control the vehicle.

11. The method of claim 10 wherein measuring torque comprises measuring automatic transmission torque.

12. The method of claim 10 wherein measuring torque comprises measuring motor torque.

13. The method of claim 12 wherein measuring motor torque comprises measuring engine torque in hybrid mode of a hybrid vehicle.

14. The method of claim 10 wherein measuring torque comprises measuring wheel torque.

15. The method of claim 10 wherein vehicle state estimation comprises transforming measured torque into active wheel torque at wheel locations.

16. The method of claim 10 wherein vehicle state estimation comprises transforming measured torque to linear active wheel torque.

17. The method of claim 10 wherein measuring torque comprises measuring brake pressure and computing brake torque from the measured brake pressure.

18. The method of claim 10 wherein vehicle state estimation comprises transforming measured torque to nonlinear active wheel torque.

19. The method of claim 10 wherein longitudinal accelerometer offset compensation estimation comprises using motor actuation toque during motor-only vehicle acceleration to compute the longitudinal accelerometer offset. Upon the completion of its computation, the offset is used to compensate the raw longitudinal acceleration to generate the compensated longitudinal acceleration

20. The method of claim 10 wherein vehicle loading estimation comprises using motor actuation toque during motor-only vehicle acceleration to compute the vehicle loading changes over its nominal value. Upon the completion of its computation, the loading change is used for various vehicle controls.

21. The method of claim 10 wherein brake effort estimation comprises converting the regenerative braking effort into an equivalent friction brake pressure effort for pure regenerative braking event such that the driver feel of regenerative braking can be reconstructed through the brake-by-wire setup to mimic the friction braking.

22. The method of claim 10 wherein brake balancing estimation comprises balancing the braking effort between regenerative braking and friction braking for a given drive braking request such that the regenerative braking can be maximized for energy recovery.

23. The method of claim 10 wherein regenerative brake redistribution estimation comprises taking away certain portion of the regenerative braking effort from rear wheels and generating braking effort equivalent friction braking at the front wheels such that the total braking effort stay the same and the vehicle stability is maintained.

24. The method of claim 10 wherein the brake lining friction coefficient estimation comprises using brake pressure based brake torque to compute the brake lining friction coefficient.

25. The method of claim 10 wherein acceleration reconstruction estimation can be reconstructed without using longitudinal accelerometer which is very useful when the longitudinal accelerometer sensor has faults or when the longitudinal accelerometer is not available as a standard sensor.

26. The method of claim 10 wherein enhanced wheel slip control uses the linear and nonlinear active wheel torque to estimate the road torque and force which can be used to seek the peak tire force that can further improve the slip control

38. The method of claim 10 wherein enhanced wheel slip control uses the linear and nonlinear active wheel torque to estimate the road torque and force which can be used to seek the peak tire force that can further improve the slip control

27. A vehicle state estimation method, comprising:

obtaining a measured torque by measuring at least one of the following;

actuation torque, braking torque, automatic transmission torque, motor torque, engine torque and wheel torque;

using the measured torque to formulate a vehicle state estimation for vehicle control, the vehicle state estimation including at least one of the following;

longitudinal accelerometer offset compensation estimation, vehicle loading estimation, brake effort estimation, brake balancing estimation, regenerative brake redistribution estimation, brake lining friction coefficient estimation, acceleration reconstruction estimation and enhanced wheel slip control estimation; and

applying the vehicle state estimation to control the vehicle.

28. The method of claim 27 wherein measured torque is used to compute linear active wheel torque.

29. The method of claim 27 wherein measured torque is used to compute nonlinear active wheel torque.

30. The method of claim 27 wherein measuring actuation torque comprises measuring engine torque in hybrid mode of a hybrid vehicle.

31. The method of claim 27 wherein longitudinal accelerometer offset compensation estimation comprises using motor actuation toque during motor-only vehicle acceleration to compute the longitudinal accelerometer offset. Upon the completion of its computation, the offset is used to compensate the raw longitudinal acceleration to generate the compensated longitudinal acceleration

32. The method of claim 27 wherein vehicle loading estimation comprises using motor actuation toque during motor-only vehicle acceleration to compute the vehicle loading changes over its nominal value. Upon the completion of its computation, the loading change is used for various vehicle controls

33. The method of claim 27 wherein brake effort estimation comprises converting the regenerative braking effort into an equivalent friction brake pressure effort for pure regenerative braking event such that the driver feel of regenerative braking can be reconstructed through the brake-by-wire setup to mimic the friction braking.

34. The method of claim 27 wherein brake balancing estimation comprises balancing the braking effort between regenerative braking and friction braking for a given drive braking request such that the regenerative braking can be maximized for energy recovery

35. The method of claim 27 wherein regenerative brake redistribution estimation comprises taking away certain portion of the regenerative braking effort from rear wheels and generating braking effort equivalent friction braking at the front wheels such that the total braking effort stay the same and the vehicle stability is maintained

36. The method of claim 27 wherein the brake lining friction coefficient estimation comprises using brake pressure based brake torque to compute the brake lining friction coefficient.

37. The method of claim 27 wherein acceleration reconstruction estimation can be reconstructed without using longitudinal accelerometer which is very useful when the longitudinal accelerometer sensor has faults or when the longitudinal accelerometer is not available as a standard sensor.