Lane departure warning and avoidance system with warning modification criteria

• US 20070164852A1
• Filed: 01/19/2006
• Published: 07/19/2007
• Est. Priority Date: 01/19/2006
• 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: Litkouhi, Bakhtiar
• Granted Patent: US 7,388,475 B2
• Time in Patent Office: Days
• US Class Current: 340/435
• 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: B60Q 9/008 for anti-collision purposes
• CPC Class Codes: B60T 2201/08 Lane monitoring; Lane Keeping Systems
• CPC Class Codes: B60T 2201/082 using alarm actuation
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 10/20 including control of steering systems
• CPC Class Codes: B60W 10/22 including control of suspension systems
• CPC Class Codes: B60W 2050/0026 Lookup tables or parameter maps
• CPC Class Codes: B60W 2050/0049 Signal offset
• CPC Class Codes: B60W 2050/0215 Sensor drifts or sensor failures
• CPC Class Codes: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2510/0652 Speed change rate
• CPC Class Codes: B60W 2510/182 Brake pressure, e.g. of fluid or between pad and disc
• CPC Class Codes: B60W 2510/20 Steering systems
• CPC Class Codes: B60W 2520/14 Yaw
• CPC Class Codes: B60W 2520/20 Sideslip angle
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 30/12 Lane keeping
• CPC Class Codes: B60W 50/02 Ensuring safety in case of control system failures, e.g. by diagnosing, circumventing or fixing failures
• CPC Class Codes: B60W 50/14 Means for informing the driver, warning the driver or prompting a driver intervention
• CPC Class Codes: B62D 15/029 : Steering assistants using warnings or proposing actions to the driver without influencing the steering system
• CPC Class Codes: G08G 1/161 : Decentralised systems, e.g. inter-vehicle communication
• CPC Class Codes: G08G 1/167 : Driving aids for lane monitoring, lane changing, e.g. blind spot detection

Abstract

A lane departure detection/avoidance and data fusion system adapted for use with a vehicle and by an operator, includes at least one lane-marking sensor, at least one condition sensor, and a controller communicatively coupled to the sensors, and configured to determine a condition deviation, and compare the condition deviation to a pre-determined condition threshold, so as to improve system identification of operator engagement, lane departure detection upon curves, and detection of performance degradation.

Claims

1. A lane departure detection and data fusion system adapted for use by an operator and with a vehicle traveling upon a thoroughfare, said system comprising:

at least one lane-marking sensor configured to detect the position of the vehicle relative to at least one lane marking;

at least one condition sensor configured to determine at least one actual condition of the vehicle; and

a controller communicatively coupled to the lane marking and condition sensors, and configured to determine the distance or time to lane crossing between the vehicle and said at least one lane marking, alert the operator when the distance is less than a predetermined warning threshold, compare the actual condition to a predetermined estimated condition, so as to determine a condition deviation, and reduce the warning threshold, when the condition deviation is greater than a pre-determined tolerance factor (ε

).

2. The system as claimed in claim 1,

said controller being further configured to determine a time to lane crossing by the vehicle, and alert the operator when the time to lane crossing is less than a predetermined warning threshold.

3. The system as claimed in claim 1;

and

a map database presenting a plurality of position points;

a locator device communicatively coupled to the database, and configured to determine the location of the vehicle and match the location with a first of said position points,

said controller being further configured to compare the actual condition to a predetermined estimated condition relative to the location of the vehicle.

4. The system as claimed in claim 1,

said vehicle including a steering wheel,

said at least one condition sensor being configured to detect the actual steering wheel angle (δ

),

said controller being further configured to compare δ

to a predetermined estimated steering angle (δ

_R) based on the location of the vehicle.

5. The system as claimed in claim 4,

said controller being further configured to reduce the threshold by a pre-determined value, wherein said value is a function of δ

_R, δ

, and a calibration parameter (λ

).

6. The system as claimed in claim 5,

said controller being further configured to reduce the threshold by the formula:

λ

(ε

|δ

_R−

δ

|).

7. The system as claimed in claim 4,

said vehicle presenting a steering gear ratio (G), a wheel base length (L), and side slip angles for the front axle (α

_f), and for the rear axle (α

_r),

said lane-marking sensor, condition sensor, and controller being cooperatively configured to determine a current radius of curvature (R) for the thoroughfare,

said estimated steering wheel angle (δ

_R) being determined as a function of G, R, α

_f, α

_r, and L.

8. The system as claimed in claim 7,

said estimated steering angle being determined according to the formula

δ

_R=G[(C₁/R)+(α

_f−

α

_r)], where C₁=(180/π

)L.

9. The system as claimed in claim 1,

said at least one condition sensor being configured to detect an actual brake condition,

said controller being further configured to compare the actual brake condition to a predetermined engaged brake condition threshold, and suppress the warning threshold, when the actual condition does not comply with the condition threshold.

10. The system as claimed in claim 1,

said at least one condition sensor being configured to detect an actual steering angle,

said controller being further configured to determine a rate of steering angle change, compare the rate of steering angle change to a predetermined threshold, and suppress the warning threshold, when the actual condition does not comply with the condition threshold.

11. The system as claimed in claim 1,

said at least one condition sensor being configured to detect an actual acceleration pedal travel or force or engine rpm condition,

said controller being further configured to determine a rate of acceleration pedal force or travel or engine rpm condition change, compare the rate of acceleration pedal travel or force or engine rpm condition change to a predetermined threshold, and suppress the warning threshold, when the acceleration pedal travel or force or engine rpm change condition does not comply with the condition threshold.

12. The system as claimed in claim 1,

said vehicle including a steering wheel,

said at least one condition sensor being configured to detect the angle of the steering wheel, and the actuation condition of a corresponding turn signal,

said controller being further configured to compare the steering wheel angle and turn signal actuation conditions to corresponding predetermined condition thresholds, and suppress the warning threshold, when the actual conditions do not comply with the condition thresholds.

13. The system as claimed in claim 1,

said at least one condition sensor being configured to detect the suspension displacement of the vehicle,

said controller being further configured to compare the suspension displacement to a predetermined suspension displacement threshold, and suppress the warning threshold, when the displacement does not comply with the displacement threshold.

14. The system as claimed in claim 1,

said vehicle having a gear shift,

said at least one condition sensor being configured to detect a manual shift of the gear shift,

said controller being further configured to suppress the warning threshold upon the occurrence of a manual shift of the gear shift.

15. The system as claimed in claim 1,

said at least one condition sensor being configured to detect the absolute lateral acceleration of the vehicle,

said controller being further configured to compare the absolute lateral acceleration to a predetermined lateral acceleration threshold, and suppress the warning threshold, when the absolute lateral acceleration does not comply with the predetermined threshold.

16. The system as claimed in claim 15,

said at least one condition sensor being configured to detect the lateral velocity with respect to said at least one lane marking,

said controller being further configured to compare the lateral velocity with respect to said at least one lane marking to a predetermined lateral velocity with respect to said at least one lane marking threshold, and suppress the warning threshold, when the lateral velocity with respect to said at least one lane marking does not comply with the condition threshold.

17. The system as claimed in claim 1,

said at least one lane-marking sensor, at least one condition sensor, or controller being spaced from the vehicle, and controlled by a third party.

18. A lane deviation detection system adapted for use with a vehicle, said system comprising:

at least one lane-marking sensor configured to detect the position of the vehicle relative to at least one lane marking, and including an image processor and at least one camera;

at least one condition sensor configured to determine at least one actual condition of the vehicle; and

a controller communicatively coupled to the lane-marking and condition sensors, presenting a warning algorithm, and configured to determine the distance between the vehicle and said at least one lane marking, alert the operator when the distance is less than a predetermined warning threshold, compare the actual condition to a predetermined calibration condition threshold, and adjust the warning algorithm, when the actual condition does not comply with the condition threshold.

19. The system as claimed in claim 18,

said image processor being configured to determine a pitch or vertical displacement condition for said at least one camera,

said controller being further configured to suppress the warning threshold if the pitch or vertical displacement is greater than a predetermined camera threshold.

20. The system as claimed in claim 18,

said controller being further configured to adjust the lane-marking sensor, when the actual condition does not comply with the condition threshold.

21. A computer program for execution by at least one electronic device associated with a vehicle traveling upon a thoroughfare, wherein said vehicle has an operator, at least one lane-marking sensor, and at least one condition sensor, and said program is configured to receive lane marking and condition data from the sensors, determine the distance between the vehicle and said at least one lane marking, generate an electric warning flag so as to alert the operator when the distance or time to lane crossing is less than a predetermined warning threshold, compare the condition data to a predetermined estimated condition threshold, and modify the warning threshold, based on the condition data and threshold comparison.

22. The program as claimed in claim 21, wherein the program is further configured to compare the condition data to a predetermined estimated condition threshold, so as to determine a condition deviation, and modify the warning threshold, when the condition deviation is greater than a pre-determined tolerance factor.

23. The program as claimed in claim 21, wherein the program is further configured to verify the warning flag prior to alerting the operator.

24. The program as claimed in claim 23, wherein the program is further configured to verify the warning flag after receiving the condition data.

25. The program as claimed in claim 24, wherein the warning flag is generated and the condition data is received concurrently.