LANE KEEPING ASSISTANCE EQUIPMENT FOR AUTOMOTIVE VEHICLES

• US 20070233343A1
• Filed: 03/29/2007
• Published: 10/04/2007
• Est. Priority Date: 03/29/2006
• Status: Active Grant

• Current Assignee: Subaru Corp.
• Original Assignee: Fuji Heavy Industries Limited (Subaru Corp.)
• Inventors: KUDO, Shinya, OYAMA, Hajime, SAITO, Toru
• Granted Patent: US 7,890,231 B2
• Time in Patent Office: Days
• US Class Current: 701/41
• CPC Class Codes: B62D 1/28 non-mechanical , e.g. following a line or other known markers
• CPC Class Codes: B62D 1/286 Systems for interrupting non-mechanical steering due to driver intervention
• 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

Abstract

A lane keeping assistance equipment is provided, for traveling while accurately following a lane marking, without any accompanying temporary stoppages or causing discomfort to the driver. The lane keeping assistance equipment 1 has a lane marking detecting means 2 for detecting lane marking locations LR, LL; a sideways distance detecting means 32 for detecting a distance R between an automotive vehicle and the lane marking locations LR, LL; a control means 3 for creating and setting a travel target point GP at a location separated from the lane marking location LR, LL and transmitting a signal to a response unit A for causing travel on the travel target point concerned; an intervening steering detecting means 31 for detecting an intervening steering act by the driver; and a measuring means 35 for measuring an elapsed time, wherein the control means 3 updates a distance amount Rgp in correspondence with changes in the above-mentioned distance R, during a time period T total, covering the continuation of the driver'"'"'s intervening steering acts and the elapsing of a prescribed time T lap after the intervening steering acts end, and after the above-mentioned prescribed time T lap elapses, the control means 3 also causes the above-mentioned updated distance amount to become fixed.

Claims

1. A lane keeping assistance equipment loaded on an automotive vehicle having a response motion unit for controlling a steering of the automotive vehicle traveling on a traffic lane between lane markings, comprising:

a lane marking detecting means for detecting a lane marking location;

a sideways distance detecting means for detecting, based on said lane marking location detected by said lane marking detecting means, a sideways distance between the lane marking location and the automotive vehicle;

a control means for performing lane keeping controls by creating and setting a travel target point at a position apart from said lane marking location, and transmitting a signal to the response motion unit for the automotive vehicle to travel on the travel target point involved;

an intervening steering act detecting means for detecting intervening steering acts by a driver driving the automotive vehicle; and

a measuring means for measuring an elapsing time after said intervening steering detected by said intervening steering act detecting means,

wherein said control means updates a distance amount between said travel target point and the lane marking location, in correspondence with changes in the distance between said lane marking location and the automotive vehicle, at a time period during a continuing intervening steering act by the driver and an elapsing of a prescribed time after the ending of the steering act, and after said prescribed time elapses, sets the distance amount to said updated distance amount at the end of the elapsing of the prescribed time.

2. The lane keeping assistance equipment of claim 1, wherein said control means changes said prescribed time based on a road curvature.

3. The lane keeping assistance equipment of claim 2, wherein said control means shortens said prescribed time based on said road curvature.

4. The lane keeping assistance equipment of claim 1, wherein if a vehicle speed inputted from a vehicle sensor is greater than a predetermined threshold value, said prescribed time is shortened from when said vehicle speed is less than said threshold value.

5. The lane keeping assistance equipment of claim 1, wherein if said updated distance amount is smaller than a prescribed distance set beforehand, as said travel target point approaches a left-right lane marking location, then if an intervention from a steering act by said driver is not being detected, said control means increases said distance amount and causes said travel target point to move in a direction toward a center of a driving lane.

6. The lane keeping assistance equipment of claim 5, wherein the moving of said travel target point ends at the point in time when said distance amount becomes equal to said prescribed distance or at the point in time when the distance amount becomes greater than the prescribed distance.

7. The lane keeping assistance equipment of claim 5, further comprising a wakefulness estimation means for estimating a wakefulness of the driver, wherein if a determination is made from an estimation result by said wakefulness estimation means that the driver'"'"'s wakefulness is falling, then said control means increases said prescribed distance.

8. The lane keeping assistance equipment of claim 1, wherein said intervening steering detecting means detects an intervening steering act by said driver at least at an occurrence of a steering torque inputted from a steering torque sensor exceeding a predetermined threshold value, or at the steering torque'"'"'s being inputted continuously in excess of a predetermined continuation time period, or at a differential value of a steering angle of a steering wheel, inputted from a steering angle sensor, being in excess of a predetermined threshold value.

9. The lane keeping assistance equipment of claim 1, wherein said sideways distance detecting means selects a lane marking location at one side of the left-right lane marking locations, and detects the distance between the lane marking location and the automotive vehicle based on said lane marking location detected by the lane marking detecting means, and said control means sets the travel target point at a fixed distance frontward of the automotive vehicle, at a position separated only by said distance amount from the lane marking location at said one side, which was selected by said sideways distance detecting means.

10. The lane keeping equipment of claim 1, wherein said sideways distance detecting means calculates a center of a driving lane based on said detected lane marking location, and detects a distance between said center of the driving lane and the automotive vehicle, and said control means calculates the center of the driving lane based on said lane marking location at a fixed distance frontward of the automotive vehicle, and sets the travel target point at a position separated only by said distance from said center of the driving lane to the automotive vehicle.

11. The lane keeping assistance equipment of claim 1, wherein said sideways distance detecting means calculates a width of a driving lane based on said detected lane marking location, and detects a ratio of distances to the lane marking location and the automotive vehicle regarding said driving lane width, and said control means calculates the distance amount from said lane marking location by applying said ratio to said driving lane width at a fixed distance frontward of the automotive vehicle, and sets the travel target point at a position separated from said lane marking location only by that specific calculated distance amount.

12. The lane keeping assistance equipment of claim 1, further comprising a solid object detecting means for detecting a solid object within a picked-up image, wherein if an existence of another vehicle at an adjacent driving lane, frontward of the automotive vehicle, is detected by said solid object detecting means, then said control means does not perform an updating of said distance amount in a direction toward said detected other vehicle.

13. The lane keeping assistance equipment of claim 1, wherein if a lane marking location is not detected by said lane marking detecting means, or the automotive vehicle is turning right or turning left, or the automotive vehicle is moving to an adjacent driving lane through lane changing, then said control means interrupts the control actions of said lane keeping controls.

14. The lane keeping assistance equipment of claim 1, wherein if an edge at the side of the automotive vehicle straying from the lane marking goes over the concerned lane marking by greater than a predetermined distance to the outside, then said control means interrupts the control actions of said lane keeping controls.

15. The lane keeping assistance equipment of claim 13, wherein said control means re-starts the control actions of the lane keeping controls at the stage when, at the original driving lane or the entered driving lane, a space between the automotive vehicle'"'"'s edge and the corresponding lane marking location becomes greater than a predetermined interval.

16. The lane keeping assistance equipment of claim 13, wherein if the control actions of said lane keeping controls are interrupted, then at the re-starting time of the lane keeping controls, said control means sets as said distance amount the distance between the lane marking location detected by said sideways distance detecting means and the automotive vehicle.

17. The lane keeping assistance equipment of claim 1, wherein at a device activation time, said control means sets as said distance amount the distance between the lane marking location detected by the sideways distance detecting means and the automotive vehicle.

18. The lane keeping assistance equipment of claim 1, wherein if there are excessive steering acts of the steering wheel, then said control means completely stops the control actions of said lane keeping controls.

19. The lane keeping assistance equipment of claim 1, further comprising a wakefulness estimation means for estimating a wakefulness of the driver, wherein if a determination is made from an estimation result by said wakefulness estimation means that the driver'"'"'s wakefulness is falling, then said control means sets said travel target point at a center of a driving lane.