Automatic travel controlling device

• US 6,138,062 A
• Filed: 07/02/1997
• Issued: 10/24/2000
• Est. Priority Date: 07/15/1996
• Status: Expired due to Fees

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Usami, Masayuki
• Primary Examiner(s): LOUIS JACQUES, JACQUES H
• Application Number:
  US08/887,335
• Time in Patent Office: 1,210 Days
• Field of Search: 701/23, 701/24, 701/25, 701/27, 701/208, 701/36, 701/41, 701/117, 701/300, 701/26, 701/28, 701/301, 180/168, 180/169, 318/587, 348/116, 348/119, 340/436, 340/438, 340/439, 356/3.01, 356/3.1, 356/5.01
• US Class Current: 701/23
• 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 15/026 combined with automatic distance control, i.e. electronic tow bar
• CPC Class Codes: B62D 15/0265 Automatic obstacle avoidance by steering
• CPC Class Codes: G05D 1/0238 using obstacle or wall sensors G05D1/0246 and G05D1/0289 take precedence; lidar systems designed for anti-collision purposes G01S17/93
• CPC Class Codes: G05D 1/0246 using a video camera in combination with image processing means
• CPC Class Codes: G05D 1/0253 extracting relative motion information from a plurality of images taken successively, e.g. visual odometry, optical flow determining position or orientation from images G06T7/70
• CPC Class Codes: G05D 1/0257 using a radar radar systems designed for anti-collision purposes between land vehicles or between land vehicle and fixed obstacles G01S13/931

Abstract

An automatic travel controlling device capable of reliably guiding a vehicle along a lane even if the white lane lines cannot be detected. A laser radar device for detecting the distance to a side wall of the lane is provided to the left and right in addition to a CCD camera for detecting the white lane lines. An image from the CCD camera is supplied to a image processor ECU, and an extracted white line is supplied to a vehicle controlling ECU. A vehicle controlling ECU drives a steering actuator to perform steering control based on two white lines of the lane when detected. However, when the white lines cannot be detected, steering control based on the distances to the side walls is performed. If an obstacle is detected ahead by the laser radar device, the vehicle position is detected based on the distances to the side walls and a lane change is performed to evade the obstacle.

Claims

1. An automatic travel controlling device comprising:

first detecting means for detecting a vehicle position by detecting a lane line;

second detecting means for detecting the vehicle position by detecting the distance to a side wall of a road;

evaluating means for evaluating a detection accuracy of said first detecting means; and

controlling means for executing, based on the detection accuracy of said first detecting means, steering control based on the vehicle position that was detected by one of said first detecting means and second detecting means, wherein said evaluating means estimates a future detection accuracy based on a future travel path of the vehicle, said future travel path is a travel path accompanying a lane change by the vehicle, said evaluating means estimates said future detection accuracy lower than a predetermined value, and said controlling means executes, when said future detection accuracy is lower than the predetermined value, steering control based on the vehicle position that was detected by said second detecting means.

2. A device according to claim 1 wherein said controlling means executes, when the detection accuracy of said first detecting means is lower than a predetermined value, steering control based on the vehicle position that was detected by said second detecting means.

3. A device according to claim 1 wherein said first detecting means includes a photographing means for photographing the road ahead of the vehicle, and said evaluating means evaluates said detection accuracy based on a lane line image within a road image that was output from said photographing means.

4. A device according to claim 1 wherein said controlling means executes steering control based on the vehicle position that was detected by said first detecting means when the detection accuracy by said evaluating means subsequent to the start of a lane change has returned to the detection accuracy prior to the lane change.