Steering and braking control system

• US 9,925,988 B1
• Filed: 02/24/2017
• Issued: 03/27/2018
• Est. Priority Date: 02/24/2017
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Flord Global Technologies, LLC
• Inventors: Zwicky, Timothy D., Elwart, Shane, Hafner, Michael, Chen, Xingping, Novak, Paul James, Liu, Jiyi, Hsia, Andy Chuan, Tellis, Levasseur, Stevens, Greg Blaisdell
• Primary Examiner(s): Frejd, Russell
• Application Number:
  US15/441,278
• Time in Patent Office: 396 Days
• CPC Class Codes: B60W 10/04 including control of propulsion units
• CPC Class Codes: B60W 10/184 with wheel brakes
• CPC Class Codes: B60W 10/20 including control of steering systems
• CPC Class Codes: B60W 2050/0297 Control Giving priority to different actuators or systems
• CPC Class Codes: B60W 2050/143 Alarm means
• CPC Class Codes: B60W 2710/18 Braking system
• CPC Class Codes: B60W 2710/202 Steering torque
• CPC Class Codes: B60W 2720/14 Yaw
• CPC Class Codes: B60W 2720/406 between left and right wheel
• CPC Class Codes: B60W 30/02 Control of vehicle driving stability
• CPC Class Codes: B60W 50/0225 Failure correction strategy
• CPC Class Codes: B60W 50/029 Adapting to failures or work around with other constraints, e.g. circumvention by avoiding use of failed parts
• CPC Class Codes: B60W 50/14 Means for informing the driver, warning the driver or prompting a driver intervention
• CPC Class Codes: B62D 5/0409 Electric motor acting on the steering column
• CPC Class Codes: B62D 9/005 Emergency systems using brakes for steering
• CPC Class Codes: G01S 19/42 Determining position
• CPC Class Codes: G05D 1/0088 characterized by the autonomous decision making process, e.g. artificial intelligence, predefined behaviours using knowledge based models G06N5/00

Abstract

A control system for a vehicle includes a computer. The computer is programmed to command application of one of up to a predetermined steering torque value and up to a predetermined net asymmetric braking force value. Each predetermined force is selected to achieve a predetermined vehicle yaw torque that is at most the lesser of a first maximum yaw torque resulting from actuating a steering system and a second maximum yaw torque resulting from actuating a brake system.

Claims

1. A system, comprising a computer programmed to:

command application of one of up to a predetermined steering torque value and up to a predetermined net asymmetric braking force value, wherein each predetermined value is selected to achieve a predetermined vehicle yaw torque on a vehicle that is at most the lesser of a first maximum yaw torque resulting from actuating a steering system and a second maximum yaw torque resulting from actuating a brake system.

2. The system of claim 1, wherein the steering system includes an electric power-assisted steering actuator.

3. The system of claim 1, wherein the brake system includes two brakes coupled to respective wheels on opposite sides of the vehicle.

4. The system of claim 3, wherein the computer is programmed to command the brake system to apply a net asymmetric braking force by each brake applying a different braking force than the other brake.

5. The system of claim 1, wherein the computer is programmed to command the brake system to apply a net asymmetric braking force in response to a failure of the steering system.

6. The system of claim 5, wherein the computer is programmed to command the brake system to apply a braking force to the vehicle in response to the failure of the steering system.

7. The system of claim 5, wherein the computer is programmed to provide a warning to an occupant in response to the failure of the steering system.

8. The system of claim 1, wherein the computer is a power-steering control module.

9. The system of claim 1, further comprising the steering system.

10. The system of claim 9, further comprising the brake system.

11. A method comprising:

commanding application of one of up to a predetermined steering torque value and up to a predetermined net asymmetric braking force value, wherein each predetermined value is selected to achieve a predetermined vehicle yaw torque on a vehicle that is at most the lesser of a first maximum yaw torque resulting from actuating a steering system and a second maximum yaw torque resulting from actuating a brake system.

12. The method of claim 11, wherein the steering system includes an electric power-assisted steering actuator.

13. The method of claim 11, wherein the brake system includes two brakes coupled to respective wheels on opposite sides of the vehicle.

14. The method of claim 13, further comprising commanding the brake system to apply a net asymmetric braking force by each brake applying a different braking force.

15. The method of claim 11, further comprising commanding the brake system to apply a net asymmetric braking force in response to a failure of the steering system.

16. The method of claim 15, further comprising commanding the brake system to apply a braking force to the vehicle in response to the failure of the steering system.

17. The method of claim 15, further comprising providing a warning to an occupant in response to the failure of the steering system.