画像処理による無人搬送車の位置と方位の測定

抄録

An onboard measuring system of the location and orientation of an autonomous vehicle is presented in this paper. This system estimates the location and orientation of the vehicle on the real time basis, and by using this system, the accumulated error of the dead reckoning can be corrected.
The system consists of an onboard TV camera, signposts, a signpost detector and a microcomputer. The signpost are vertical cylinders and are put along the routes of the vehicle. Bar code patterns are printed on them. The signpost detector is composed of hard-wired logic circuits, and it can detect two signpost patterns in the field of view. The distances between the vehicle and two signposts are evaluated from their pattern widths in the image, and the microcomputer calculates the location of the vehicle on the fixed reference frame by the triangulation. The signpost detector also evaluates the relative angle between the signpost and the vehicle from the lateral position of the pattern in the image, and from this angle, the orientation of the vehicle is calculated.
Through the experiment, it was shown that the accurate location and orientation of the vehicle are obtained by this system. The processing time is 50ms and is enough for navigation of autonomous vehicles.