Lane-keep control system for vehicle

• US 6,853,884 B2
• Filed: 06/19/2002
• Issued: 02/08/2005
• Est. Priority Date: 07/13/2001
• Status: Expired due to Fees

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Sadano, On
• Primary Examiner(s): ARTHUR JEANGLAUDE, GERTRUDE
• Application Number:
  US10/173,653
• Publication Number:
  US 20030014162A1
• Time in Patent Office: 965 Days
• Field of Search: 701/1, 701/8, 701/41, 701/93, 701/96, 701/301, 340/435, 340/436, 340/903
• US Class Current: 701/1
• CPC Class Codes: B60T 2201/08 Lane monitoring; Lane Keeping Systems
• CPC Class Codes: B60T 2201/087 using active steering actuation
• CPC Class Codes: B62D 1/286 Systems for interrupting non-mechanical steering due to driver intervention
• CPC Class Codes: B62D 15/0265 Automatic obstacle avoidance by steering

Abstract

A lane-keep control system for a host-vehicle is arranged to execute a lane-keep control for moving the host-vehicle in a traveling lane, to determine whether there is an approaching-vehicle behind the host-vehicle, to increase an intervention threshold when there is the approaching vehicle behind the host-vehicle, and to suspend the lane-keep control when a steering control indicative value due to driver intervention is greater than the intervention threshold.

Claims

1. A lane-keep control system for a host-vehicle, comprising:

a control unit programmed,

to execute a lane-keep control for moving the host-vehicle in a traveling lane,

to determine whether there is an approaching-vehicle behind the host-vehicle,

to increase an intervention threshold when there is the approaching vehicle behind the host-vehicle, and

to suspend the lane-keep control when a steering control indicative value due to driver intervention is greater than the intervention threshold.

2. The lane-keep control system as claimed in claim 1, wherein the intervention threshold includes a right-lane-side intervention threshold and a left-lane-side intervention threshold which are respectively set for right and left lanes relative to the traveling lane of the host-vehicle, the control unit being programmed to detect a lane traveled by the approaching-vehicle and to increase only one of the right-lane-side and left-lane-side intervention thresholds corresponding to the detected lane traveled by the approaching-vehicle.

3. The lane-keep control system as claimed in claim 1, wherein the control unit is further programmed to detect approaching degree of the approaching-vehicle to the host-vehicle and to increase the intervention threshold according to the increase of the approaching degree.

4. The lane-keep control system as claimed in claim 3, wherein the approaching degree is obtained from an inter-vehicle distance between the host-vehicle and the approaching-vehicle.

5. The lane-keep control system as claimed in claim 3, wherein the approaching degree is obtained from a relative speed between a vehicle speed of the host-vehicle and a vehicle speed of the approaching-vehicle.

6. The lane-keep control system as claimed in claim 3, wherein the approaching degree is obtained from a margin time which is obtained by dividing an inter-vehicle distance between the host-vehicle and the approaching vehicle by a relative speed between a vehicle speed of the host-vehicle and a vehicle speed of the approaching-vehicle.

7. The lane-keep control system as claimed in claim 6, wherein the intervention threshold is increased with decrease of the margin time and is set at a constant value when the margin time is greater than a predetermined time period.

8. The lane-keep control system as claimed in claim 1, wherein the steering control indicative value due to driver intervention includes a steering wheel angle, a steering wheel angle gradient and a steering wheel torque.

9. A lane-keep control system of a host-vehicle comprising:

a steering system through which a direction of the host-vehicle is controlled;

a steering operation detecting device that detects an operation of a steering system of the host vehicle;

a lane-recognition device that recognizes a traveling lane of the host-vehicle;

a subsequent-vehicle position recognition device that detects whether there is a subsequent-vehicle behind the host-vehicle;

a control unit programmed,

to execute a lane-keep control on the basis of a recognition result of the lane-recognition device,

to determine whether a vehicle exists behind the host-vehicle, on the basis of a detection result of the subsequent-vehicle position recognition device,

to increase an intervention threshold when the vehicle exists behind the host-vehicle,

to determine whether a detection result of the steering operation detecting device is greater with the intervention threshold, and

to suspend the lane-keep control when the detection result of the steering operation detecting device is greater with the intervention threshold.

10. A method of executing a lane-keep control of a host-vehicle, comprising:

executing a lane-keep control for moving the host-vehicle in a traveling lane;

determining whether there is an approaching-vehicle behind the host-vehicle;

increasing an intervention threshold when there is the approaching vehicle behind the host-vehicle; and

suspending the lane-keep control when a steering control indicative value due to driver intervention is greater than the intervention threshold.

11. A lane-keep control system for a host-vehicle, comprising:

control executing means for executing a lane-keep control for moving the host-vehicle in a traveling lane;

determining means for determining whether there is an approaching-vehicle behind the host-vehicle;

threshold setting means for increasing an intervention threshold when there is the approaching vehicle behind the host-vehicle; and

control suspending means for suspend the lane-keep control when a steering control indicative value due to a steering operation of a driver of the host-vehicle is greater than the intervention threshold.