Vehicle-applied rear-and-side monitoring system

• US 20020087269A1
• Filed: 10/22/2001
• Published: 07/04/2002
• Est. Priority Date: 10/21/1998
• Status: Active Grant

• Current Assignee: Yazaki Corporation
• Original Assignee: Yazaki Corporation
• Inventors: Ishikawa, Naoto, Fujinami, Kazutomo, Sasaki, Kazuyuki
• Granted Patent: US 6,618,672 B2
• Time in Patent Office: Days
• US Class Current: 701/301
• CPC Class Codes: B60R 1/26 to the rear of the vehicle
• CPC Class Codes: B60R 2300/30 characterised by the type of image processing
• CPC Class Codes: B60R 2300/8066 for monitoring rearward traffic
• CPC Class Codes: G08G 1/163 involving continuous checking

Abstract

A vehicle-applied rear-and-side monitory system including an image taking means for taking an image of a rear-and-side view of the subject vehicle traveling in a lane; a characteristic point extracting means for extracting at least one point as a characteristic point from an image of a following vehicle contained in a first image, taken at a first time-point, of the rear-and-side view, the following vehicle traveling at the rear of the subject vehicle in the lane of the subject vehicle or in a neighboring lane; a corresponding point detecting means for detecting a corresponding point, corresponding to the characteristic point, in a second image taken at a second time-point following the first time-point; an optical flow forming means for forming an optical flow of the characteristic point of the following vehicle from a vector connecting the characteristic point and the corresponding point; and a dead angle area located vehicles-distance calculating means for calculating at least any one of a vehicles-distance between the subject vehicle and the following vehicle and a relative position therebetween after a time-point of disappearance of the optical flow outside an image plane of the image taking means on the basis of the optical flow formed just before the disappearance. Thus, a vehicle-applied rear-and-side monitoring system capable of monitoring an approaching degree of a following vehicle approaching from the rear of the subject vehicle in the lane of the subject vehicle in the neighboring lane can be realized.

Claims

1. A vehicle-applied rear-and-side monitoring system, comprising:

an image taking means for talking an image of rear-and-side view of a first vehicle traveling in a lane;

a characteristic point extracting means for extracting at least one point as a characteristic point from an image of a second vehicle contained in a first image, taking at a first time-point, of said rear-and-side view, said second vehicle traveling at the rear of said first vehicle in said lane or in a neighboring lane of said lane;

a corresponding point detecting means for detecting a corresponding point, corresponding to said characteristic point, in a second image taken at a second time-point following said first time-point;

an optical flow forming means for forming an optical flow of said characteristic point of said second vehicle from a vector connecting said characteristic point and said corresponding point; and

a dead angle area located vehicles-distance calculating means for calculating at least any one of a vehicles-distance between said first and second vehicles and a relative position therebetween after a time-point of disappearance of said optical flow outside an image plane of said image taking means on the basis of said optical flow formed just before said disappearance,

wherein in approaching degree of said second vehicle traveling at the rear of said first vehicle in said lane or in said neighboring lane is monitored.

2. The vehicle-applied rear-and-side monitoring system as claimed in claim 1,

wherein said dead angle area located vehicles-distance calculating means considers that said optical flow of said characteristic point of said second vehicle having arrived at a predetermined peripheral area of said image plane of said image taking means at said first time-point disappears from said image plane at said second time-point,

uses said optical flow at said first time-point as said optical flow formed just before said disappearance,

and calculates at least any one of said vehicles-distance and said relative position after said first time-point or after said second time-point.

3. The vehicle-applied rear-and-side monitoring system as claimed in claim 1, further comprising:

a dangerousness judging means for judging a degree of danger of contact or collision with said second vehicle on the basis of said vehicles-distance and said relative position having been calculated by said dead angle area located vehicles-distance calculating means.

4. The vehicle-applied rear-and-side monitoring system as claimed in claim 1, further comprising:

an alarm giving means for giving an alarm indicating danger by means of at least any one of auditory information and optical information whenever an operation for activating a direction indicator provided on said first vehicle is executed when said vehicles-distance or said relative position having been calculated by said dead angle area located vehicles-distance calculating means if within a predetermined range.

5. The vehicle-applied rear-and-side monitoring system as claimed in claim 2, wherein

said dead angle area located vehicles-distance calculating means calculates neither said vehicles-distance nor said relative position after said first time-point or after said second time-point whenever said optical flow having arrived at said predetermined peripheral area of said image plane of said image taking means at said first-time point has a directional component corresponding to a direction within a range between horizontal and upward-vertical in said rear-and-side view,

and calculates at least any one of said vehicles-distance and said relative position after said first time-point or after second time-point whenever said optical flow having arrived at said predetermined peripheral area of said image plane of said image taking means at said first time-point has a directional component corresponding to a direction within a range between horizontal (not included) and downward-vertical in said rear-and-side view.

6. The vehicle-applied rear-and-side monitoring system as claimed in claim 1, further comprising:

a second alarm giving means for giving an alarm indicating danger of a lateral collision by means of at least any one of auditory information and optical information whenever an operation for a lane change is executed within a predetermined time period from said time-point of said disappearance of said optical flow from said image plane of said image taking means.

7. The vehicle-applied rear-and-side monitoring system as claimed in claim 2, further comprising:

a second alarm giving means for giving an alarm indicating danger of a lateral collision by means of at least any one of auditory information and optical information whenever an operation for a lane change is executed within a predetermined time period from said time-point of said disappearance of said optical flow from said image plane of said image taking means.

8. The vehicle-applied rear-and-side monitoring system as claimed in claim 3, further comprising:

a second alarm giving means for giving an alarm indicating danger of a lateral collision by means of at least any one of auditory information and optical information whenever an operation for a lane change is executed within a predetermined time period from said time-point of said disappearance of said optical flow from said image plane of said image taking means.

9. The vehicle-applied rear-and-side monitoring system as claimed in claim 4, further comprising:

a second alarm giving means for giving an alarm indicating danger of a lateral collision by means of at least any one of auditory information and optical information whenever an operation for a lane change is executed within a predetermined time period from said time-point of said disappearance of said optical flow from said image plane of said taking means.

10. The vehicle-applied rear-and-side monitoring system as claimed in claim 5, further comprising:

a second alarm giving means for giving an alarm indicating danger of a lateral collision by means of at least any one of auditory information and optical information whenever an operation for a lane change is executed within a predetermined time period from said time-point of said disappearance of said optical flow from said image plane of said image taking means.

11. A vehicle-applied rear-and-side monitoring system, comprising:

an image taking means for taking an image of a rear-and-side view of a first vehicle traveling in a lane;

a characteristic point extracting means for extracting at least one point as a characteristic point from an image of a second vehicle contained in a first image, taken at a first time-point, of said rear-and-side view, said second vehicle traveling at the rear of said first vehicle in said lane or in a neighboring lane of said lane;

a corresponding point detecting means for detecting a corresponding point, corresponding to said characteristic point, in a second image taken at a second time-point following said first time-point;

an optical flow forming means for forming an optical flow of said characteristic point of said second vehicle from a vector connecting said characteristic point and said corresponding point; and

a dead angle area located vehicles-distance calculating means for calculating at least any one of a vehicles-distance between said first and second vehicles and a relative point therebetween after a time-point of disappearance of said optical flow outside an image plane of said image taking means on the basis of a plurality of optical flows including said optical flow formed just before said disappearance,

wherein an approaching degree of said second vehicle traveling at the rear of said first vehicle in said lane in said neighboring lane is monitored.

12. The vehicle-applied rear-and-side monitoring system as set forth in claim 11,

wherein the dead angle located vehicles-distance calculating means calculates the vehicles-distance or the relative position on the basis of a relative speed expected from a relative acceleration obtained from relative speeds corresponding to the plurality of optical flows.

13. The vehicle-applied rear-and-side monitoring system as set forth in claim 12,

wherein the dead angle area located vehicles-distance calculating means calculates the vehicles-distance or the relative position on the basis of both the expected relative speed and a relative traveling direction, of a second vehicle relative to a first vehicle, expected from direction change values of the plurality of optical flows.