Motor vehicle control using a dynamic feedforward approach

• US 20060069489A1
• Filed: 12/21/2004
• Published: 03/30/2006
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: BWI Company Limited SA (Shougang Corporation)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Hac, Aleksander B., Bedner, Edward J., Chen, Hsien H.
• Granted Patent: US 7,191,047 B2
• Time in Patent Office: Days
• US Class Current: 701/70
• CPC Class Codes: B60T 2230/03 Overturn, rollover
• CPC Class Codes: B60T 8/17554 specially adapted for enhancing stability around the vehicles longitudinal axle, i.e. roll-over prevention road vehicle drive control systems for roll-over prevention otherwise than by controlling a particular sub-unit B60W30/04
• CPC Class Codes: B60T 8/17555 specially adapted for enhancing driver or passenger comfort, e.g. soft intervention or pre-actuation strategies

Abstract

A control system manages yaw-plane motion, while simultaneously comprehending and managing roll motion. The system reduces excessive maneuver-induced roll motion by properly shaping yaw-plane motion, which may include increasing yaw damping and/or decreasing a yaw gain, under various conditions, to avoid excessive excitation of roll dynamics.

Claims

1. A dynamic feedforward (DFF) electronic stability control (ESC) system for a motor vehicle, comprising:

at least one sensor for providing a driver input;

a control unit implementing a dynamic reference model that provides a desired behavior based upon the driver input, the control unit implementing a feedforward control that determines an ESC differential brake force based upon the desired behavior, wherein the control unit converts the ESC differential brake force into a delta velocity (DVLR) command; and

an electronic stability control (ESC) actuator coupled to the control unit and receiving the DVLR command, wherein the ESC actuator controls a motor vehicle subsystem responsive to the DVLR command to provide a desired correction to an associated motor vehicle.

2. The system of claim 1, wherein the driver input includes a steering angle and a vehicle speed of the associated motor vehicle.

3. The system of claim 1, wherein the reference model models one of a desired motor vehicle yaw rate and a desired motor vehicle roll angle.

4. The system of claim 1, wherein parameters of the reference model are modified to achieve a desired motor vehicle characteristic.

5. The system of claim 4, wherein the desired motor vehicle characteristic is one of a motor vehicle yaw rate and a motor vehicle roll angle.

6. The system of claim 4, wherein the reference model is represented by a transfer function that has one zero and two poles.

7. The system of claim 4, wherein the reference model is represented by a transfer function that has two zeroes and four poles.

8. The system of claim 4, wherein the reference model is represented by a transfer function that has three zeroes and four poles.

9. The system of claim 1, wherein the ESC differential brake force is represented by a transfer function that has at least three zeroes and three poles.

10. A control system for a motor vehicle that coordinates yaw-plane motion and roll motion of the motor vehicle, the system comprising:

at least one sensor for providing a plurality of driver inputs, wherein the driver inputs include a motor vehicle steering angle and a motor vehicle speed;

a control unit implementing a reference model that provides a desired yaw rate based upon the driver inputs, the control unit implementing a roll motion prediction model which predicts when roll motion of the vehicle may be severely excited by yaw-plane motion, the control unit implementing a plant model algorithm that provides a predicted yaw rate based upon the driver inputs, the control unit modifying the desired yaw rate when roll motion excitation exceeds a desired level, the control unit determining an error term based upon the desired yaw rate and the predicted yaw rate and providing a delta velocity (DVLR) command based on the error term to manage the roll motion excitation; and

an electronic stability control (ESC) actuator coupled to the control unit and receiving the DVLR command, wherein the ESC actuator controls a motor vehicle brake subsystem responsive to the DVLR command to provide a desired correction to the motor vehicle.

11. The system of claim 10, wherein parameters of the reference model are modified to adjust the desired yaw rate to reduce yaw-plane motion of the motor vehicle.

12. The system of claim 10, wherein a lateral acceleration and rate of change in the lateral acceleration are predicted from the steering angle and speed, and wherein a linear combination of the lateral acceleration and the rate of change in the lateral acceleration are used to predict excessive roll motion.

13. The system of claim 12, wherein parameters of the reference model are modified to adjust the desired yaw rate to reduce yaw-plane motion of the motor vehicle when the predicted roll motion is above a threshold value.

14. The system of claim 13, wherein a rate of change in the parameters is reduced when the linear combination is decreasing.

15. The system of claim 10, wherein the reference model is modified by at least one of increasing a damping ratio of a second order filter, gain adjustment and natural frequency adjustment.

16. A control system for a motor vehicle that coordinates yaw-plane motion and roll motion of the motor vehicle, the system comprising:

at least one sensor for providing a plurality of driver inputs, wherein the driver inputs include a motor vehicle steering angle and a motor vehicle speed, the at least one sensor also providing an actual yaw rate;

a control unit implementing a reference model that receives the steering angle and the speed and provides a desired yaw rate, the control unit implementing a roll motion prediction model which predicts when roll motion of the vehicle may be severely excited by yaw-plane motion, the control unit modifying the desired yaw rate when roll motion excitation exceeds a desired level, the control unit determining an error term based upon the desired yaw rate and the actual yaw rate and providing a delta velocity (DVLR) command based on the error term to manage the roll motion excitation; and

an electronic stability control (ESC) actuator coupled to the control unit and receiving the DVLR command, wherein the ESC actuator controls a vehicle brake subsystem responsive to the DVLR command to provide a desired correction to an associated motor vehicle.

17. The system of claim 16, wherein parameters of the reference model are modified to adjust the desired yaw rate to reduce a yaw-plane motion of the motor vehicle.

18. The system of claim 16, wherein a lateral acceleration and rate of change in the lateral acceleration are predicted from the steering angle and speed, and wherein a linear combination of the lateral acceleration and the rate of change in the lateral acceleration are used to predict excessive roll motion.

19. The system of claim 18, wherein parameters of the reference model are modified to adjust the desired yaw rate to reduce yaw-plane motion of the motor vehicle when the predicted roll motion is above a threshold value.

20. The system of claim 19, wherein a rate of change in the parameters is reduced when the linear combination is decreasing.

21. The system of claim 16, wherein the reference model is modified by at least one of increasing a damping ratio of a second order filter, gain adjustment and natural frequency adjustment.