Lane deviation avoidance system

• US 20050177308A1
• Filed: 02/04/2005
• Published: 08/11/2005
• Est. Priority Date: 02/06/2004
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Matsumoto, Shinji, Tange, Satoshi, Naito, Genpei, Nakajima, Hidekazu, Shimakage, Masayasu
• Granted Patent: US 7,778,759 B2
• Time in Patent Office: Days
• US Class Current: 701/301
• CPC Class Codes: B60T 2201/08 Lane monitoring; Lane Keeping Systems
• CPC Class Codes: B60T 2201/083 using active brake actuation
• CPC Class Codes: B60T 8/17557 specially adapted for lane departure prevention road vehicle drive control systems for lane keeping otherwise than by controlling a particular sub-unit B60W30/12
• CPC Class Codes: B60W 10/04 including control of propulsion units
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 30/12 Lane keeping

Abstract

A lane deviation avoidance system is arranged to execute a lane deviation avoidance control of controlling a vehicle behavior of the host vehicle so as to avoid the host vehicle from deviating from a traveling lane when the lane deviation tendency is detected, to suppress the driving force when the lane deviation tendency is detected, and to set a controlled variable of the lane deviation avoidance control according to a degree of the suppression of the driving force.

Claims

1. A lane deviation avoidance system comprising:

a driving force generating unit generating a driving force according to a demanded quantity; and

a control unit configured,

to detect a lane deviation tendency of a host vehicle,

to execute a lane deviation avoidance control of controlling a vehicle behavior of the host vehicle so as to avoid the host vehicle from deviating from a traveling lane when the lane deviation tendency is detected,

to detect the demanded quantity indicative of a demanded driving force,

to suppress the driving force when the lane deviation tendency is detected, and

to set a controlled variable of the lane deviation avoidance control according to a degree of the suppression of the driving force.

2. The lane deviation avoidance system as claimed in claim 1, wherein the controlled variable of the lane deviation avoidance control is increased according to the increase of the suppression degree of the driving force.

3. The lane deviation avoidance system as claimed in claim 1, wherein the control unit is further configured to estimate an estimated lane deviation quantity of the host vehicle with respect to a traveling lane, to calculate a target yawing moment for avoiding the lane deviation of the host vehicle according to the suppression degree of the driving force and the estimated lane deviation quantity, and to generate the target yawing moment.

16. The lane deviation avoidance system as claimed in claim 1, wherein the control unit is further arranged to cancel the suppression of the driving force when it is estimated from the operation of determining the lane deviation tendency that the host vehicle is recovered from the lane deviation.

17. The lane deviation avoidance system as claimed in claim 1, wherein the control unit is further arranged to limit a fluctuation quantity of the driving force, which is caused by one of the suppression of the driving force and the cancellation of suppressing the driving force.

4. A lane deviation avoidance system comprising:

a driving force generating unit generating a driving force according to a driving force demanded quantity; and

a control unit configured,

to detect a lane deviation tendency of a host vehicle,

to control a vehicle behavior of the host vehicle to avoid the host vehicle from deviating from a traveling lane when the lane deviation tendency is detected,

to detect a driving force demanded quantity,

to estimate a reaction force which is oppositely generated between the driving force according to the driving force demanded quantity and a force for the lane deviation avoidance control, and

to suppress the driving force by a quantity corresponding to the reaction force when the lane deviation tendency is detected.

5. The lane deviation avoidance system as claimed in claim 4, wherein the control unit is further arranged to calculate a deceleration controlled variable of avoiding the lane deviation on the basis of a difference between the driving force corresponding to the driving force demanded quantity and the reaction force, and to execute a braking force control so as to generate a deceleration corresponding to the deceleration controlled variable.

6. The lane deviation avoidance system as claimed in claim 5, wherein the control unit is further arranged to detect an engine braking force, wherein the deceleration controlled quantity is calculated by subtracting a sum of the driving force corresponding to the driving force demanded quantity and the engine braking force from the reaction force.

7. A lane deviation avoidance system comprising:

a driving force generating unit generating a driving force according to a driving force demanded quantity; and

a control unit configured,

to detect a lane deviation tendency of a host vehicle,

to detect the driving force demanded quantity,

to estimate a reaction force which is oppositely generated between the driving force according to the driving force demanded quantity and a controlling force for the lane deviation avoidance control,

to calculate a driving/braking force for generating a deceleration corresponding to the reaction force by subtracting the reaction force from the driving force when the lane deviation tendency is detected, and

to generate the driving/braking force.

8. A lane deviation avoidance system comprising:

a driving force generating unit generating a driving force according to a driving force demanded quantity;

a control unit configured,

to detect a lane deviation tendency of a host vehicle,

to control a vehicle behavior of the host vehicle to avoid the host vehicle from deviating from a traveling lane when the lane deviation tendency is detected,

to detect the driving force demanded quantity,

to detect a running resistance force of the host vehicle, and

to suppress the driving force according to the running resistance force when the lane deviation tendency is detected.

9. The lane deviation avoidance system as claimed in claim 8, wherein a driving force corresponding to the running resistance force is employed as a lower limit of suppressing the driving force.

10. The lane deviation avoidance system as claimed in claim 8, wherein a driving force corresponding to the running resistance force is employed as a lower limit of suppressing the driving force when the driving force corresponding to the driving force demanded quantity is greater than the driving force corresponding to the running resistance force.

11. The lane deviation avoidance system as claimed in claim 8, wherein the operation of suppressing the driving force is cancelled when the driving force corresponding to the driving force demanded quantity is smaller than or equal to the driving force corresponding to the running resistance force.

12. The lane deviation avoidance system as claimed in claim 8, wherein the control unit is further configured to determine an acceleration intent of a driver, and to suppress the driving force only when it is determined that the driver does not have the acceleration intent.

13. The lane deviation avoidance system as claimed in claim 12, wherein the control unit is further configured to determine that the driver has the acceleration intent when the driving force demanded quantity is greater than or equal to a predetermined threshold.

14. The lane deviation avoidance system as claimed in claim 8, wherein the control unit is further configured to set the controlled variable of the lane deviation avoidance control according to the degree of the suppression of the driving force.

15. The lane deviation avoidance system as claimed in claim 8, wherein the control unit is further arranged to generate a yawing moment to avoid the host vehicle from deviating from the traveling lane.

18. A lane deviation avoidance system comprising:

a driving force generating unit generating a driving force according to a demanded quantity; and

a control unit configured,

to detect a lane deviation tendency of a host vehicle,

to execute a lane deviation avoidance control of controlling a vehicle behavior of the host vehicle so as to avoid the host vehicle from deviating from a traveling lane of the host vehicle when the lane deviation tendency is detected,

to detect the demanded quantity indicative of a demanded driving force,

to suppress the driving force when the lane deviation tendency is detected,

to estimate a lane change intent of a driver on the basis of the demanded quantity, and

to recover the driving force when it is estimated that the driver has the lane change intent.

23. The lane deviation avoidance system as claimed in claim 18, wherein the driving force is recovered at a changing rate when it is estimated that the driver has the lane change intent.

24. The lane deviation avoidance system as claimed in claim 18, wherein the control unit is further arranged to estimate that the driver has a lane change intent when the demanded quantity becomes greater or equal to a first threshold which is a sum of a decision value and the demanded quantity taken at a moment that the lane deviation avoidance control is started.

25. The lane deviation avoidance system as claimed in claim 24, wherein the first threshold value is varied according to the demanded quantity.

26. The lane deviation avoidance system as claimed in claim 25, wherein the control unit is further arranged to estimate that the driver does not have the lane change intent when the demanded quantity once becomes greater than the first threshold and becomes smaller than a second threshold which is smaller than the first threshold.

27. The lane deviation avoidance system as claimed in claim 26, wherein the second threshold is set at the demanded quantity taken at a moment that the lane deviation avoidance control is started.

28. The lane deviation avoidance system as claimed in claim 18, wherein the control unit is further arranged to determine that the driver does not have the lane change intent when it is determined that the host vehicle is not put in the lane deviation tendency.

19. A lane deviation avoidance system comprising:

a driving force generating unit generating a driving force according to a demanded quantity; and

a control unit configured,

to detect a lane deviation tendency of a host vehicle,

to execute a lane deviation avoidance control of controlling a vehicle behavior of the host vehicle so as to avoid the host vehicle from deviating from a traveling lane of the host vehicle when the lane deviation tendency is detected,

to detect a demanded quantity indicative of a demanded driving force,

to suppress the driving force when the lane deviation tendency is detected,

to estimate a lane change intent of a driver on the basis of the demanded quantity, and

to suppress a controlled variable of the lane deviation avoidance control when it is estimated that the driver has the lane change intent.

20. The lane deviation avoidance system as claimed in claim 19, wherein the control unit is further arranged to recover the driving force when it is estimated that the driver has the lane change intent.

21. The lane deviation avoidance system as claimed in claim 20, wherein the control unit is further arranged to calculate a target yawing moment for avoiding the lane deviation, to generate the target yawing moment, and to suppress the target yawing moment according to the recovered driving force when it is estimated that the driver has the lane change intent.

22. The lane deviation avoidance system as claimed in claim 20, wherein the control unit is further arranged to calculate a deceleration controlled variable for avoiding the lane deviation, to execute a deceleration control based on the deceleration controlled variable, and to suppress the deceleration controlled variable according to the recovered driving force when it is estimated that the driver has an lane change intent.

29. A lane deviation avoidance system comprising:

a control unit configured,

to detect a lane deviation tendency of a host vehicle;

to execute a lane deviation avoidance control of controlling a vehicle behavior of the host vehicle so as to avoid the host vehicle from deviating from a traveling lane of the host vehicle when the lane deviation tendency is detected,

to detect a demanded quantity indicative of a demanded driving force;

to calculate a target driving force by decreasing the demanded quantity when the lane deviation is detected,

to execute a driving force control for generating the target driving force when the lane deviation is detected, and

to calculate the target driving force on the basis of the demanded quantity at a moment that the lane deviation avoidance control is started.

30. The lane deviation avoidance system as claimed in claim 29, wherein the control unit is further arranged to calculate a controlled variable of the lane deviation avoidance control on the basis of an increment of the demanded quantity relative to the demanded quantity at a moment that the lane deviation avoidance control is started.

32. The lane deviation avoidance system as claimed in claim 29, wherein the lane deviation avoidance control includes one of a yawing moment control of generating a yawing moment for avoiding the lane deviation and a deceleration control for avoiding the lane deviation.

31. A lane deviation avoidance system comprising:

a driving force generating unit generating a driving force according to a demanded quantity; and

a control unit configured,

to detect a lane deviation tendency of a host vehicle;

to execute a lane deviation avoidance control of controlling a vehicle behavior of the host vehicle so as to avoid the host vehicle from deviating from a traveling lane of the host vehicle when the lane deviation tendency is detected,

to detect the demanded quantity indicative of a demanded driving force;

to suppress the driving force generated by the driving force generating unit when the lane deviation tendency is detected, and

to calculate a controlled variable of the lane deviation avoidance control on the basis of an increment of the demanded quantity relative to the demanded quantity detected at a moment that the lane deviation avoidance control is started.

33. A method of avoiding a lane deviation of a host vehicle, comprising:

detecting a lane deviation tendency of a host vehicle;

executing a lane deviation avoidance control of controlling a vehicle behavior of the host vehicle so as to avoid the host vehicle from deviating from a traveling lane when the lane deviation tendency is detected;

generating a driving force according to a demanded quantity;

detecting the demanded quantity indicative of a demanded driving force;

suppressing the driving force when the lane deviation tendency is detected; and

setting a controlled variable of the lane deviation avoidance control according to a degree of the suppression of the driving force.

34. A lane deviation avoidance system comprising:

lane deviation detecting means for detecting a lane deviation tendency of a host vehicle;

lane deviation avoidance controlling means for controlling a vehicle behavior of the host vehicle so as to avoid the host vehicle from deviating from a traveling lane when the lane deviation tendency is detected;

driving force generating means for generating a driving force according to a demanded quantity;

driving force demanded quantity detecting means for detecting the demanded quantity indicative of a demanded driving force;

driving force suppressing means for suppressing the driving force when the lane deviation tendency is detected; and

the driving force controlling means setting a controlled variable of the lane deviation avoidance control according to a degree of the suppression of the driving force.