Method and system for lane centering control

• US 20080091318A1
• Filed: 10/11/2006
• Published: 04/17/2008
• Est. Priority Date: 10/11/2006
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Zhang, Haicen, Lee, Yong H., Deng, Weiwen
• Granted Patent: US 8,983,765 B2
• Time in Patent Office: Days
• US Class Current: 701/41
• CPC Class Codes: B62D 15/025 Active steering aids, e.g. helping the driver by actively influencing the steering system after environment evaluation B62D1/28 takes precedence
• CPC Class Codes: B62D 6/003 in order to control vehicle yaw movement, i.e. around a vertical axis B62D6/007 takes precedence
• CPC Class Codes: G05D 1/0244 using reflecting strips
• CPC Class Codes: G05D 1/0257 using a radar radar systems designed for anti-collision purposes between land vehicles or between land vehicle and fixed obstacles G01S13/931
• CPC Class Codes: G05D 2201/0213 Road vehicle, e.g. car or truck

Abstract

A system for lane centering control for a vehicle having a user-operable steering device is disclosed. The system includes a set of sensors for sensing the vehicle speed, yaw rate, and steering device angle, a target path tracker configured for tracking the target path of the vehicle, a processor responsive to the set of sensors for predicting the path of the vehicle, a controller responsive to the set of sensors, the target path tracker, and the processor, and productive of a lane centering control signal, and an active front steering actuator responsive to the control signal and productive of steering assistance to the steering device. The controller includes a processing circuit responsive to executable instructions for producing the steering assistance to the steering device to reduce a difference between the predicted path and the target path, thereby serving to maintain lane centering of the vehicle.

Claims

1. A system for lane centering control for a vehicle having a user-operable steering device, comprising:

a set of sensors for sensing the vehicle speed, yaw rate, and steering device angle;

a target path tracker configured for tracking the target path of the vehicle;

a processor responsive to the set of sensors for predicting the path of the vehicle;

a controller responsive to the set of sensors, the target path tracker, and the processor, and productive of a lane centering control signal; and

an active front steering actuator responsive to the control signal and productive of steering assistance to the steering device;

wherein the controller comprises a processing circuit responsive to executable instructions for;

producing the steering assistance to the steering device to reduce a difference between the predicted path and the target path, thereby serving to maintain lane centering of the vehicle.

2. The system of claim 1, wherein:

the target path tracker comprises a vision system.

3. The system of claim 2, wherein:

the target path tracker further comprises a radar system, a map database with a global positioning system sensor, or a combination of both

4. The system of claim 1, wherein the control signal is responsive to a feedforward control signal based on a sensed curvature and a sensed heading angle of the target path.

5. The system of claim 4, wherein the control signal is responsive to a feedback control signal based on a sensed curvature of the target path.

6. The system of claim 5, wherein the control signal is responsive to a path preview control signal based on information from the set of sensors and information relating to the target path.

7. The system of claim 1, wherein the control signal is responsive to a set of conditional control signals for controlling the operability of the control signal.

8. The system of claim 7, wherein the set of conditional control signals comprises signals responsive to enabling conditions, operating conditions, activating conditions, or a combination comprising at least one of the foregoing conditions.

9. The system of claim 8, wherein the vehicle comprises an adaptive cruise control, a lane departure warning apparatus, a first switch for enabling the lane centering control signal, a second switch for enabling the adaptive cruise control, and a third switch for enabling the lane departure warning apparatus;

and further wherein

the enabling conditions comprises all of the following;

detection of a request to enable the lane centering control signal;

detection of a request to enable the adaptive cruise control of the vehicle;

detection of a request to enable the lane departure warning apparatus; and

, detection that all input signals to the controller are normal.

10. The system of claim 8, wherein the vehicle comprises an adaptive cruise control, a lane departure warning apparatus, a first switch for enabling the lane centering control signal, a second switch for enabling the adaptive cruise control, and a third switch for enabling the lane departure warning apparatus;

and further wherein;

the operating conditions comprises all of the following;

detection of the lane departure warning apparatus being engaged;

detection of the adaptive cruise control being engaged;

detection of the vehicle speed being within a defined range;

detection of the vehicle longitudinal acceleration and lateral acceleration being less than defined values;

detection of the target path curvature ahead being greater than a defined value;

and, detection of the user being in operable contact with the steering device.

11. The system of claim 10, wherein the vehicle further comprises at least one of an anti-lock brake system, a traction control system, and a vehicle stability control system;

and further wherein;

the operating conditions comprises detection of the status of the at least one of an anti-lock brake system, a traction control system, and a vehicle stability control system being disengaged.

12. The system of claim 8, wherein the vehicle comprises a turn signal switch and a brake switch;

and further wherein

the activating conditions comprises all of the following;

detection of the turn signal switch being off;

detection of the brake switch being off;

detection of the steering device angle being less than a defined value; and

, detection of the steering device rate of change of angle being less than a defined value.

13. A method for lane centering control for a vehicle having a user-operable steering device, the vehicle disposed to traverse a target path, the method comprising:

sensing the vehicle speed, yaw rate, and steering device angle;

tracking the target path of the vehicle;

sensing a predicted path of the vehicle;

in response to the sensed vehicle speed, yaw rate, and steering device angle, and in response to information relating to the target path and predicted path of the vehicle, producing a lane centering control signal; and

in response to the lane centering control signal, actuating an active front steering actuator to produce steering assistance to the steering device to reduce a difference between the predicted path and the target path, thereby serving to maintain lane centering of the vehicle.

14. The method of claim 13, wherein the tracking comprises tracking the target path based on vision sensor.

15. The method of claim 14, wherein the tracking further comprises tracking the target path based on a radar system, a map database with a global positioning system sensor, or a combination of both.

16. The method of claim 13, wherein the producing a lane centering control signal comprises producing a lane centering control signal in response to a feedforward control signal based on a sensed curvature and a sensed heading angle of the target path.

17. The method of claim 16, wherein the producing a lane centering control signal further comprises producing a lane centering control signal in response to a feedback control signal based on a sensed curvature of the target path.

18. The method of claim 17, wherein the producing a lane centering control signal further comprises producing a lane centering control signal in response to a path preview control signal based on information from the set of sensors and information relating to the target path, the path preview control signal serving to provide smooth path tracking.

19. The method of claim 13, wherein the producing a lane centering control signal comprises producing a lane centering control signal in response to a set of conditional control signals for controlling the operability of the lane centering control signal, wherein the set of conditional control signals comprises signals responsive to enabling conditions, operating conditions, activating conditions, or a combination comprising at least one of the foregoing conditions.

20. The method of claim 19, wherein the enabling conditions comprises all of the following:

detection of a request to enable the lane centering control signal;

detection of a request to enable an adaptive cruise control of the vehicle;

detection of a request to enable a lane departure warning apparatus of the vehicle; and

, detection that all diagnostic signals of the vehicle are normal.

21. The method of claim 19, wherein the operating conditions comprises all of the following:

detection of a lane departure warning apparatus of the vehicle being engaged;

detection of an adaptive cruise control of the vehicle being engaged;

detection of the vehicle speed being within a defined range;

detection of the vehicle longitudinal acceleration and lateral acceleration being less than defined values;

detection of the target path curvature ahead being greater than a defined value; and

, detection of the user being in operable contact with the steering device.

22. The method of claim 21, wherein the operating conditions further comprises detection of the status of at least one of an anti-lock brake system, a traction control system and a vehicle stability control system of the vehicle being disengaged.

23. The method of claim 19, wherein the activating conditions comprises all of the following:

detection of a turn signal switch of the vehicle being off;

detection of a brake switch of the vehicle being off;

detection of the steering device angle being less than a defined value; and

, detection of the steering device rate of change of angle being less than a defined value.