Tire side slip angle control for an automotive vehicle using steering peak seeking actuators

• US 20040074693A1
• Filed: 10/16/2002
• Published: 04/22/2004
• Est. Priority Date: 10/16/2002
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Brown, Todd Allen, Mattson, Keith Glenn
• Granted Patent: US 6,840,343 B2
• Time in Patent Office: Days
• US Class Current: 180/446
• 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 17/0195 characterised by the regulation being combined with other vehicle control systems conjoint control of vehicle sub-units including control of suspension systems B60W10/22
• CPC Class Codes: B60G 2400/0521 Roll rate
• CPC Class Codes: B60G 2400/0522 Pitch rate
• CPC Class Codes: B60G 2400/0523 Yaw rate
• CPC Class Codes: B60G 2400/104 lateral or transversal with regard to vehicle
• CPC Class Codes: B60G 2400/106 longitudinal with regard to vehicle, e.g. braking
• CPC Class Codes: B60G 2400/204 Vehicle speed
• CPC Class Codes: B60G 2400/41 Steering angle
• CPC Class Codes: B60G 2400/412 of steering wheel or column
• CPC Class Codes: B60G 2400/64 Wheel forces, e.g. on hub, spindle or bearing
• CPC Class Codes: B60G 2400/822 Road friction coefficient determination affecting wheel traction
• CPC Class Codes: B60G 2600/1877 Adaptive Control
• CPC Class Codes: B60G 2600/70 Computer memory; Data storage, e.g. maps for adaptive control
• CPC Class Codes: B60G 2800/212 Transversal; Side-slip during cornering
• CPC Class Codes: B60G 2800/702 Improving accuracy of a sensor signal
• CPC Class Codes: B60G 2800/912 Attitude Control; levelling control
• CPC Class Codes: B60G 2800/92 ABS - Brake Control
• CPC Class Codes: B60T 2230/02 Side slip angle, attitude angle, floating angle, drift angle
• CPC Class Codes: B60T 2260/02 Active Steering, Steer-by-Wire
• CPC Class Codes: B60T 8/17552 : responsive to the tire sideslip angle or the vehicle body slip angle
• CPC Class Codes: B60W 10/184 : with wheel brakes
• CPC Class Codes: B60W 10/20 : including control of steering systems
• CPC Class Codes: B60W 2530/20 : Tyre data
• CPC Class Codes: B60W 30/045 : Improving turning performance
• CPC Class Codes: B62D 6/04 : responsive only to forces disturbing the intended course of the vehicle, e.g. forces acting transversely to the direction of vehicle travel

Abstract

A stability control system (24) for an automotive vehicle includes a plurality of sensors sensing the dynamic conditions of the vehicle. The controller (26) is coupled to the sensors. The controller (26) determines a lateral force in response to measured vehicle conditions, determines a slip angle in response to measured vehicle conditions, determines a first steering actuator angle change to decrease the slip angle until the lateral force increases, and thereafter determines a second steering actuator angle change to increase the slip angle until the lateral force decreases.

Claims

1. A control system for an automotive vehicle having a steering actuator comprising:

a plurality of sensors generating a plurality of signals corresponding to a dynamic condition of the vehicle; and

a controller coupled to the plurality of sensors, said controller determining a lateral force in response to measured vehicle conditions, determining a slip angle in response to measured vehicle conditions, determining a first steering actuator angle change to decrease the slip angle until the lateral force increases, thereafter, determining a second steering actuator angle change to increase the slip angle until the lateral force decreases.

2. A system as recite in claim 1 wherein said steering actuator comprises a front right wheel actuator and a front left wheel actuator.

3. A system as recite in claim 2 wherein said front right wheel steering actuator and said front left steering actuator are independently controllable.

4. A system as recite in claim 3 wherein said controller generates a front right control signal and a front left control signal in determining a first steering actuator angle change and determining a second steering actuator angle change.

5. A system as recite in claim 1 wherein said steering actuator comprises a rear steering actuator and a front steering actuator.

6. A system as recite in claim 1 wherein said controller determines a rear steering control signal in determining a first steering actuator angle change and determining a second steering actuator angle change.

7. A method of controlling a vehicle having a steering actuator comprising:

determining a lateral force in response to measured vehicle conditions;

determining a slip angle in response to measured vehicle conditions;

determining a first steering actuator angle change to decrease the slip angle until the lateral force increases;

controlling the steering actuator in response to the first steering actuator change angle;

thereafter, determining a second steering actuator angle change to increase the slip angle until the lateral force decreases; and

controlling the steering actuator in response to the second steering actuator change angle.

8. A method as recited in claim 7 wherein determining a first steering actuator angle change to decrease the slip angle until the lateral force increases is performed independent of a handwheel position.

9. A method as recited in claim 7 wherein controlling the steering actuator in response to the first steering actuator change angle and controlling the steering actuator in response to the second steering actuator change angle comprises controlling a front steering actuator.

10. A method as recited in claim 7 wherein controlling the steering actuator in response to the first steering actuator change angle and controlling the steering actuator in response to the second steering actuator change angle comprises controlling a rear steering actuator.

11. A method as recited in claim 7 wherein controlling the steering actuator in response to the first steering actuator change angle and controlling the steering actuator in response to the second steering actuator change angle comprises controlling a front right steering actuator.

12. A method as recited in claim 7 wherein controlling the steering actuator in response to the first steering actuator change angle and controlling the steering actuator in response to the second steering actuator change angle comprises controlling a front left steering actuator.

13. A method of controlling a vehicle having a steering actuator comprising:

determining a lateral force in response to measured vehicle conditions; and

controlling the steering actuator in response to the lateral force to maximize the lateral force.

14. A method as recited in claim 13 wherein controlling the steering actuator comprises changing a slip angle to maximize the lateral force.

15. A method as recited in claim 13 wherein controlling the steering actuator comprises changing a steering angle to increase the lateral force until the lateral force decreases, then changing the steering angle until the lateral force increases.