Apparatus and method of recognizing vehicle travelling behind

• US 20020154217A1
• Filed: 04/22/2002
• Published: 10/24/2002
• Est. Priority Date: 04/20/2001
• Status: Active Grant

• Current Assignee: Fuji Jukogyo KK (Subaru Corp.)
• Original Assignee: Fuji Jukogyo KK (Subaru Corp.)
• Inventors: Ikeda, Atsushi
• Granted Patent: US 6,734,787 B2
• Time in Patent Office: Days
• US Class Current: 348/148
• CPC Class Codes: G01S 11/12 using electromagnetic waves other than radio waves
• CPC Class Codes: G06V 20/584 of vehicle lights or traffic lights
• CPC Class Codes: G06V 20/588 Recognition of the road, e.g. of lane markings; Recognition of the vehicle driving pattern in relation to the road
• CPC Class Codes: G06V 2201/08 Detecting or categorising vehicles
• CPC Class Codes: G08G 1/0965 responding to signals from another vehicle, e.g. emergency vehicle
• CPC Class Codes: G08G 1/166 for active traffic, e.g. moving vehicles, pedestrians, bikes
• CPC Class Codes: G08G 1/167 Driving aids for lane monitoring, lane changing, e.g. blind spot detection

Abstract

Images of objects existing behind a first vehicle are detected to obtain distance data on the objects in relation to the first vehicle for recognizing one of the objects as a second vehicle travelling behind the first vehicle based on the distance data. The type of the second vehicle travelling behind is determined in size based on the images. It is further determined whether the second vehicle is an emergency vehicle based on the images.

Claims

1. An apparatus for recognizing a vehicle travelling behind comprising:

a detector for detecting images of objects existing behind a first vehicle in which the apparatus is installed to obtain distance data on the objects in relation to the first vehicle, thus recognizing one of the objects as a second vehicle travelling behind the first vehicle based on the distance data;

a first determining unit for determining the type of the second vehicle in size based on the images; and

a second determining unit for determining whether the second vehicle is an emergency vehicle based on the images.

2. The apparatus according to claim 1, wherein the detector has a pair of cameras, one of the cameras taking an image as a reference image of the objects existing behind the first vehicle and the other taking an image of the objects for comparison with the reference image in stereo image processing to obtain three-dimensional distance distribution of the objects from the first vehicle.

3. The apparatus according to claim 2, wherein the detector recognizes the one of the objects as the second vehicle travelling behind based on a distance of the one of the objects from the first vehicle in the three-dimensional distance distribution.

4. The apparatus according to claim 2, wherein the first determining unit compares the one of the objects recognized as the second vehicle travelling behind with reference objects in size to determine the second vehicle as a large vehicle, a medium-size or compact vehicle or two-wheeled vehicle.

5. The apparatus according to claim 2, wherein the second determining unit compares intensity on a specific area on the one of the objects recognized as the second vehicle travelling behind with a reference intensity in the images, the specific area depending on the type of the second vehicle, and determines that the second vehicle is equipped with a flashing light, thus deciding that the second vehicle is the emergency vehicle, if the intensity on the specific unit is higher than the reference intensity and exhibits periodical change.

6. The apparatus according to claim 1 further comprising an informing unit for informing a driver driving the first vehicle of information on the results determined by the first and second determining units.

7. A method of recognizing a vehicle travelling behind comprising the steps of:

detecting images of objects existing behind a first vehicle to obtain distance data on the objects in relation to the first vehicle, thus recognizing one of the objects as a second vehicle travelling behind the first vehicle based on the distance data;

determining the type of the second vehicle in size based on the images; and

determining unit for determining whether the second vehicle is an emergency vehicle based on the images.

8. The method according to claim 7, wherein the detecting step includes the steps of:

taking an image as a reference image of the objects existing behind the first vehicle; and

taking an image of the objects for comparison with the reference image in stereo image processing to obtain three-dimensional distance distribution of the objects from the first vehicle.

9. The method according to claim 8, wherein the detecting step further includes the step of recognizing the one of the objects as the second vehicle travelling behind based on a distance of the one of the objects from the first vehicle in the three-dimensional distance distribution.

10. The method according to claim 8, wherein the type determining step includes the step of comparing the one of the objects recognized as the second vehicle travelling behind with reference objects in size to determine the second vehicle as a large vehicle, a medium-size or compact vehicle or two-wheeled vehicle.

11. The method according to claim 8, wherein the emergency-vehicle determining step includes the step of:

comparing intensity on a specific area on the one of the objects recognized as the second vehicle travelling behind with a reference intensity in the images, the specific area depending on the type of the second vehicle; and

determining that the second vehicle is equipped with a flashing light, thus deciding that the second vehicle is the emergency vehicle, if the intensity on the specific unit is higher than the reference intensity and exhibits periodical change.

12. The method according to claim 7 further comprising the step of informing a driver driving the first vehicle of information on the results determined by the determining steps.