VEHICLE HANDLING DYNAMICS CONTROL USING FULLY ACTIVE SUSPENSION

• US 20170113506A1
• Filed: 10/22/2015
• Published: 04/27/2017
• Est. Priority Date: 10/22/2015
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: XU, Li, HROVAT, Davor David, DEUR, Josko, CORIC, Mirko, TSENG, Eric Hongtei
• Granted Patent: US 9,975,391 B2
• Time in Patent Office: Days
• CPC Class Codes: B60G 17/0162 mainly during a motion involving steering operation, e.g. cornering, overtaking B60G17/0164 takes precedence
• CPC Class Codes: B60G 2400/41 Steering angle
• CPC Class Codes: B60G 2500/40 Steering
• CPC Class Codes: B60G 2600/182 Active control means
• CPC Class Codes: B60G 2800/244 Oversteer
• CPC Class Codes: B60G 2800/246 Understeer

Abstract

Arrangements (e.g., method, apparatus, computer-readable non-transitory media embodying a program) for compensating for understeer or oversteer behavior in a vehicle having a fully active suspension, including: determining whether an understeer or oversteer condition exists; determining a compensation torque needed to correct the understeer or oversteer condition; and generating the compensation torque by using the fully active suspension to shift tire loads between tires.

Claims

1. A method for compensating for understeer or oversteer behavior in a vehicle having a fully active suspension, comprising:

determining whether an understeer or oversteer condition exists;

determining a compensation torque needed to correct the understeer or oversteer condition; and

generating the compensation torque by using the fully active suspension to shift tire loads between tires.

2. The method of claim 1, wherein generating the compensation torque comprises:

reducing normal force on driven wheels of the vehicle, using the fully active suspension and/or

balancing normal forces on tires of one axle while increasing normal forces on tires of another axle of the vehicle, using the fully active suspension.

3. The method of claim 1, wherein generating the compensation torque comprises:

balancing front tire normal forces when an understeer condition is present and/or

increasing rear tire normal forces when an understeer condition is present.

4. The method of claim 1, wherein generating the compensation torque comprises:

balancing front rear normal forces when an oversteer condition is present and/or

increasing front tire normal forces when an oversteer condition is present.

5. A method of compensating for understeer or oversteer behavior in a throttle-on situation in a vehicle having a fully active suspension, comprising:

estimating desired vehicle motion;

determining whether an understeer condition or an oversteer condition exists;

determining a compensation torque needed to achieve the desired vehicle motion; and

generating the compensation torque by using the fully active suspension to adjust tire loads dynamically.

6. The method of claim 5, wherein generating the compensation torque comprises:

reducing normal force on driven wheels of the vehicle, using the fully active suspension and/or

balancing normal forces on tires of one axle while increasing normal forces on tires of another axle of the vehicle, using the fully active suspension.

7. The method of claim 5, wherein generating the compensation torque comprises:

balancing front tire normal forces when an understeer condition is present and/or

increasing rear tire normal forces when an understeer condition is present.

8. The method of claim 5, wherein generating the compensation torque comprises:

balancing front rear normal forces when an oversteer condition is present and/or

increasing front tire normal forces when an oversteer condition is present.

9. A method of providing sustained compensation for a driving condition in a vehicle having a fully active suspension, comprising:

estimating desired vehicle motion;

determining if an understeer condition or an oversteer condition exists;

determining a compensation torque needed to achieve the desired vehicle motion; and

stiffening one of front and rear suspensions of the vehicle and softening the other of the front and rear suspensions, to generate the compensation torque using the fully active suspension.

10. The method of claim 9, comprising stiffening the rear suspension and softening the front suspension of the vehicle, when an understeer condition exists.

11. The method of claim 9, comprising stiffening the front suspension and softening the rear suspension of the vehicle, when an oversteer condition exists.

12. A method for providing compensation for a predicted driving condition in a vehicle having a fully active suspension, comprising:

estimating desired vehicle motion;

predicting if a driving condition will occur;

determining a compensation torque needed to achieve the desired vehicle motion, in view of the predicted driving condition; and

generating the compensation torque using the fully active suspension, in anticipation of the predicted driving condition.

13. The method of claim 12, wherein the predicted driving condition is an oversteer condition.

14. The method of claim 13, wherein generating the compensation torque comprises stiffening the front suspension and softening the rear suspension using the fully active suspension system, in anticipation of the anticipated oversteer condition.

15. The method of claim 14, wherein generating the compensation torque comprises increasing inner front tire and outer rear tire normal forces using the fully active suspension system, in anticipation of the anticipated oversteer condition.

16. The method of claim 12, wherein the predicted driving condition is an understeer condition.

17. The method of claim 12, wherein generating the compensation torque comprises stiffening the rear suspension and softening the front suspension using the fully active suspension system, in anticipation of the anticipated understeer condition.

18. The method of claim 12, wherein generating the compensation torque comprises increasing inner rear tire and outer front tire normal forces using the fully active suspension system, in anticipation of the anticipated understeer condition.

19. The method of claim 12, wherein:

the predicted driving condition is a body roll of the vehicle; and

adjusting the body roll of the vehicle in one of a tilting direction and a counter-tilting direction using the fully active suspension, to generate the compensation torque.

20. The method of claim 19, further comprising determining at least one of desired front lateral tire force and rear lateral tire force.

21. The method of claim 19, further comprising determining at least one of desired toe angle and desired camber angle.

22. The method of claim 19, wherein adjusting the body roll of the vehicle includes affecting toe angle and/or camber angle.

23. A vehicle control system, comprising:

a fully active suspension; and

a controller configured to;

estimate desired vehicle motion;

predict if a driving condition will occur;

determine a compensation torque needed to achieve the desired vehicle motion, in view of the predicted driving condition; and

generate the compensation torque using the fully active suspension, in anticipation of the predicted driving condition.

24. The vehicle control system of claim 23, wherein the controller is configured to stiffen the front suspension and soften the rear suspension to generate the compensation torque, in anticipation of an anticipated oversteer condition.

25. The vehicle control system of claim 23, wherein the controller is configured to increase inner front tire and outer rear tire normal forces to generate the compensation torque, in anticipation of an anticipated oversteer condition.

26. The vehicle control system of claim 23, wherein the controller is configured to stiffen the rear suspension and soften the front suspension to generate the compensation torque, in anticipation of an anticipated understeer condition.

27. The vehicle control system of claim 23, wherein the controller is configured to:

reduce normal force on driven wheels of the vehicle; and

/or

balance normal forces on tires of one axle while increasing normal forces on tires of another axle of the vehicle, to generate the compensation torque.

28. The vehicle control system of claim 23, wherein the controller is configured to:

balance front tire normal forces and/or increase rear tire normal forces, to generate an understeer compensation torque.

29. The vehicle control system of claim 23, wherein the controller is configured to:

balance front rear normal forces and/or increase front tire normal forces to generate an oversteer compensation torque.