Browse Prior Art Database

Relative Velocity Detector for Vehicles Traveling in Other Lanes

IP.com Disclosure Number: IPCOM000113985D
Original Publication Date: 1994-Oct-01
Included in the Prior Art Database: 2005-Mar-27
Document File: 2 page(s) / 63K

Publishing Venue

IBM

Related People

Echigo, T: AUTHOR

Abstract

Disclosed is a system for detecting the relative velocity of a vehicle traveling in another lane of a highway by means of a camera mounted on the roof of a moving car. This system outputs the relative velocity of a traveling vehicle every 66 ms.

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This is the abbreviated version, containing approximately 80% of the total text.

Relative Velocity Detector for Vehicles Traveling in Other Lanes

      Disclosed is a system for detecting the relative velocity of a
vehicle traveling in another lane of a highway by means of a camera
mounted on the roof of a moving car.  This system outputs the
relative velocity of a traveling vehicle every 66 ms.

      The wide-angle lens covers a large field of vision extending
backward and forward from the side of the vehicle.  Distortion by the
wide-angle lens can be corrected by projecting images onto a
semi-sphere.  Whether or not a moving vehicle exists in the image
determined from the differential image between an odd and an even
field, that is, every 17 ms, in several small windows that watch
small areas, as shown in the figure.  When a sum of absolute values
of the differential image is larger than a threshold, the existence
of a moving vehicle can be .  inferred.Because the camera is set
slantingly from the roof of the moving car to the road, so that the
background image of a moving vehicle always shows the smooth road.
The distance of a vehicle moved in 17 ms can be measured from the
motion contour in the differential image, and the positions of the
windows aafter 66 ms are inferred.  After the windows start to track
a moving vehicle, the next positions of the windows are determined by
correlation between neighboring areas of the motion contour.  Each
window outputs the relative velocity of a part of the moving vehicle
independently,after succe...