PREDICTIVE VEHICLE STABILITY CONTROL METHOD

• US 20150105990A1
• Filed: 12/16/2014
• Published: 04/16/2015
• Est. Priority Date: 06/21/2012
• Status: Active Grant

• Current Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Original Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Inventors: Grogg, John A., Chimner, Christian T.
• Granted Patent: US 9,248,833 B2
• Time in Patent Office: Days
• US Class Current: 701/71
• CPC Class Codes: B60T 2201/14 Electronic locking-differential
• CPC Class Codes: B60T 7/12 for automatic initiation; for initiation not subject to will of driver or passenger limiting speed of vehicles other than rail vehicles B60K31/00
• CPC Class Codes: B60T 8/1755 Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve road vehicle drive control systems for control of driving stability otherwise than by controlling a particular sub-unit B60W30/02
• CPC Class Codes: B60W 30/02 Control of vehicle driving stability
• CPC Class Codes: B60W 40/114 Yaw movement

Abstract

A method of controlling vehicle stability includes the steps of obtaining a measured yaw rate from the vehicle, generating a predicted yaw rate based on the measured yaw rate, calculating a first error signal based on a difference between the measured yaw rate and a desired yaw rate, calculating a second error signal based on a difference between the predicted yaw rate and the desired yaw rate, and sending a selected one of the first and second error signals to a yaw controller to conduct stability control. The predicted yaw rate can be generated by sending the measured yaw rate through a lead filter.

Claims

1. A method of controlling stability of a vehicle, comprising:

obtaining a measured yaw rate from the vehicle;

generating a predicted yaw rate based on the measured yaw rate;

calculating a first error signal based on a difference between the measured yaw rate and a desired yaw rate;

calculating a second error signal based on a difference between the predicted yaw rate and the desired yaw rate; and

sending a selected one of the first and second error signal to a yaw controller to conduct stability control.

2. The method of claim 1, wherein the predicted yaw rate is generated by sending the measured yaw rate through a lead filter.

3. The method of claim 1, wherein the sending step comprises sending a maximum of the first and second error signals to the yaw controller to conduct stability control during an oversteering condition.

4. The method of claim 3, wherein the sending step further comprises sending a minimum of the first and second error signals to the yaw controller to conduct stability control during an understeering condition.

5. The method of claim 1, wherein the sending step comprises sending a minimum of the first and second error signals to the yaw controller to conduct stability control during an understeering condition.

6. The method of claim 1, further comprising calculating a saturated value of at least one of the first and second error signal before sending said selected one of the first and second error signal to the yaw controller.

7. The method of claim 1, further comprising sending said selected one of the first and second error signal through a deadhand filter before sending said selected one of the first and second error signals to the yaw controller.

8. The method of claim 1, wherein the yaw controller sends a yaw command to at least one of an anti-lock braking system and an electronic limited slip differential to conduct stability control.

9. A method of controlling stability of a vehicle, comprising;

obtaining a measured yaw rate from the vehicle;

generating a predicted yaw rate based on the measured yaw rate, wherein the predicted yaw rate is obtained by sending the measured yaw rate through a lead filter;

calculating a first error signal based on a difference between the measured yaw rate and a desired yaw rate;

calculating a second error signal based on a difference between the predicted yaw rate and the desired yaw rate;

sending a selected one of a saturated value of the first and second error signal to a yaw controller, which generates a yaw command; and

outputting the yaw command to at least one of an anti-lock braking system and an electronic limited slip differential to conduct stability control.

10. The method of claim 9, wherein the sending step comprises sending a maximum of the saturated value of first and second error signals to the yaw controller to conduct stability control during an oversteering condition.

11. The method of claim 10, wherein the sending step further comprises sending a minimum of the saturated value of the first and second error signals to the yaw controller to conduct stability control during an understeering condition.

12. The method of claim 9, wherein the sending step comprises sending a minimum of the saturated value of first and second error signals to the yaw controller to conduct stability control during an understeering condition.

13. The method of claim 9, further comprising sending said one of the saturated value of first and second error signal through a deadhand filter before sending said greater of the first and second error signals to the yaw controller.

14. A vehicle stability control system, comprising:

an electronic limited slip differential;

an electronic control unit (ECU) containing a yaw controller and carrying out a yaw control strategy, wherein the yaw controller outputs a yaw command to the electronic limited slip differential to conduct stability control, wherein the yaw control strategy includes

obtaining a measured yaw rate from the vehicle;

generating a predicted yaw rate based on the measured yaw rate;

calculating a first error signal based on a difference between the measured yaw rate and a desired yaw rate;

calculating a second error signal based on a difference between the predicted yaw rate and the desired yaw rate; and

sending a selected one of the first and second error signal to the yaw controller to conduct stability control.

15. The system of claim 14, wherein the ECU generates the predicted yaw rate by sending the measured yaw rate through a lead filter.

16. The system of claim 14, wherein the ECU sends a maximum of the first and second error signals to the yaw controller to conduct stability control during an oversteering condition.

17. The system of claim 16, wherein the ECU also sends a minimum of the first and second error signals to the yaw controller to conduct stability control during an understeering condition.

18. The system of claim 14, wherein the ECU sends a minimum of the first and second error signals to the yaw controller to conduct stability control during an understeering condition.

19. The system of claim 14, wherein the controller also calculates a saturated value of at least one of the first and second error signal before sending said one of the first and second error signal to the yaw controller.

20. The system of claim 14, wherein the controller sends said selected one of the first and second error signal through a deadband filter before sending said selected one of the first and second error signals to the yaw controller.

21. The system of claim 14, further comprising an anti-lock braking system, wherein the controller sends the yaw command to the anti-lock braking system for stability control.