Branch-Lane Entry Judging System

• US 20090157286A1
• Filed: 06/19/2008
• Published: 06/18/2009
• Est. Priority Date: 06/22/2007
• Status: Active Grant

• Current Assignee: Subaru Corp.
• Original Assignee: Fuji Heavy Industries Limited (Subaru Corp.)
• Inventors: Saito, Toru, Maruyama, Tasuku
• Granted Patent: US 8,447,484 B2
• Time in Patent Office: Days
• US Class Current: 701/117
• CPC Class Codes: B60W 30/12 Lane keeping
• CPC Class Codes: B60W 30/16 Control of distance between vehicles, e.g. keeping a distance to preceding vehicle

Abstract

A branch-lane entry judging system includes a traffic-line detecting means for detecting traffic lines on right and left sides of a vehicle, a length and width detecting means for detecting lengths and widths of the traffic lines in a real space, a lane-type judging means for judging types of the traffic lines and a type of a lane in which the vehicle is running, a branch-lane detecting means for detecting a branch lane when one of the traffic lines changes from a solid line to a broken line having a predetermined length and a predetermined width, the branch lane existing near the changed traffic line, and a branch-lane entry judging means for judging that the vehicle will enter the branch lane when the vehicle moves toward the branch lane or a directional indicator is operated toward the branch lane while the branch lane is detected.

Claims

1. A branch-lane entry judging system comprising:

traffic-line detecting means configured to detect traffic lines on right and left sides of a vehicle;

length and width detecting means configured to detect lengths and widths in a traveling direction of the vehicle on a real space of the traffic lines detected by the traffic-line detecting means;

lane-type judging means configured to judge types of the traffic lines and judge a type of a lane in which the vehicle is running, on the basis of a result of detection performed by the length and width detecting means;

branch-lane detecting means configured to detect the existence of a branch lane when detecting, on the basis of the result of detection performed by the length and width detecting means, that one of the traffic lines changes from a solid line to a broken line having a predetermined length and a predetermined width, the branch lane existing near the changed traffic line; and

branch-lane entry judging means configured to judge that the vehicle will enter the branch lane when the vehicle moves toward the branch lane or a directional indicator is operated toward the branch lane while the branch-lane detecting means is detecting the branch lane.

2. The branch-lane entry judging system according to claim 1, further comprising:

history holding means configured to hold a history showing that the broken line having the predetermined length and the predetermined width was detected as a solid line in the previous sampling period,

wherein it is judged, with reference to the history held by the history holding means, that the one of the traffic lines changes from the solid line to the broken line.

3. The branch-lane entry judging system according to claim 1, wherein an acceleration-prohibiting signal for prohibiting acceleration of the vehicle is output when the branch-lane entry judging means that the vehicle will enter the branch lane.

4. The branch-lane entry judging system according to claims 1, wherein a deceleration signal for decelerating the vehicle is output when the length and width detecting means detects that both the traffic lines on the right and left sides of the vehicle have changed to solid lines while a predetermined time passes or while the vehicle runs by a predetermined distance after the branch-lane entry judging means judges that the vehicle will enter the branch lane.

5. The branch-lane entry judging system according to claim 4, wherein the output of the deceleration signal is stopped when at least one of the traffic lines on the right and left sides of the vehicle is not detected by the length and width detecting means after the output of the deceleration signal starts.

6. The branch-lane entry judging system according to claim 4, wherein the output of the deceleration signal is stopped when a predetermined time passes, the vehicle runs by a predetermined distance, or a speed of the vehicle falls below a predetermined speed after the output of the deceleration signal starts.

7. The branch-lane entry judging system according to claim 5, wherein a signal for stopping constant-speed running control on the vehicle is output when the output of the deceleration signal is stopped.

8. The branch-lane entry judging system according to claim 6, wherein a signal for stopping constant-speed running control on the vehicle is output when the output of the deceleration signal is stopped.

9. The branch-lane entry judging system according to claim 4, wherein the output of the deceleration signal is stopped when a curvature of a road becomes more than or equal to a predetermined curvature after the length and width detecting means detects that both the traffic lines on the right and left sides of the vehicle have changed to the solid lines.

10. The branch-lane entry judging system according to claim 3, wherein the output of the acceleration-prohibiting signal is stopped when the length and width detecting means detects that the one of the traffic lines is the broken line having the predetermined length and the predetermined width while a predetermined time passes or the vehicle runs by a predetermined distance after the branch-lane entry judging means judges that the vehicle will enter the branch lane.

11. The branch-lane entry judging system according to claim 9, wherein a signal for returning to constant-speed running control on the vehicle is output when the output of the deceleration signal or the acceleration-prohibiting signal is stopped.

12. The branch-lane entry judging system according to claim 10, wherein a signal for returning to constant-speed running control on the vehicle is output when the output of the deceleration signal or the acceleration-prohibiting signal is stopped.

13. The branch-lane entry judging system according to claims 3, further comprising:

preceding-vehicle detecting means configured to detect a preceding vehicle,

wherein, when the acceleration-prohibiting signal or the deceleration signal is output, a deceleration calculated from a speed of the preceding vehicle and a distance between the vehicle and the preceding vehicle detected by the preceding-vehicle detecting means is output, and

wherein the output deceleration and a deceleration based on the acceleration-prohibiting signal or the deceleration signal are compared, and control is performed while giving priority to one of the decelerations having a larger absolute value.

14. The branch-lane entry judging system according to claim 4, further comprising:

preceding-vehicle detecting means configured to detect a preceding vehicle,

wherein, when the acceleration-prohibiting signal or the deceleration signal is output, a deceleration calculated from a speed of the preceding vehicle and a distance between the vehicle and the preceding vehicle detected by the preceding-vehicle detecting means is output, and

wherein the output deceleration and a deceleration based on the acceleration-prohibiting signal or the deceleration signal are compared, and control is performed while giving priority to one of the decelerations having a larger absolute value.

15. The branch-lane entry judging system according to claims 3, further comprising:

preceding-vehicle detecting means configured to detect a preceding vehicle,

wherein, when the preceding vehicle is detected by the preceding-vehicle detecting means, a signal for returning to preceding-vehicle follow control so that the vehicle follows the preceding vehicle is output.

16. The branch-lane entry judging system according to claims 4, further comprising:

preceding-vehicle detecting means configured to detect a preceding vehicle,

wherein, when the preceding vehicle is detected by the preceding-vehicle detecting means, a signal for returning to preceding-vehicle follow control so that the vehicle follows the preceding vehicle is output.

17. The branch-lane entry judging system according to claims 3, wherein, when the directional indicator is operated in a direction opposite the branch lane, a signal for returning to constant-speed running control on the vehicle is output.

18. The branch-lane entry judging system according to claims 4, wherein, when the directional indicator is operated in a direction opposite the branch lane, a signal for returning to constant-speed running control on the vehicle is output.