Apparatus for displaying current location

• US 5,003,306 A
• Filed: 02/13/1989
• Issued: 03/26/1991
• Est. Priority Date: 02/15/1988
• Status: Expired due to Term

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Matsumoto, Yoshiyuki, Iihoshi, Akira, Nakamura, Yukinobu, Takahashi, Tsuneo
• Primary Examiner(s): Orsino, Joseph A.
• Assistant Examiner(s): SWARTHOUT, BRENT
• Application Number:
  US07/310,337
• Time in Patent Office: 771 Days
• Field of Search: 340/995, 340/990, 340/988, 73/178 R, 364/449, 364/460, 364/424.01
• US Class Current: 340/995.22
• CPC Class Codes: G01C 21/30 Map- or contour-matching

Abstract

There is disclosed an apparatus for displaying a current location of a running body in which a constantly changing location of the running body on a two-dimensional coordinates is successively computed, while detecting a running distance of the running body and a running direction of the same, and the current location of said running body is displayed renewally, in accordance with the data thus computed, on a display screen having a map previously displayed thereon. The apparatus comprises means for extracting a linear running portion from current location of the running body obtained by storing data of the current location, means for extracting a linear road portion from adjoining roads on the map which corresponds to the linear running portion extracted from the current location means for effecting matching between the extracted linear running portion and linear road portion, depending on their positional relationship and means for putting the current location, onto the road to which the matching has been effected.

Claims

1. An apparatus for displaying a current location of a running body in which a continuously changing location of the running body on X-Y coordinates is successively computed and a current location of the running body is displayed, in accordance with data thus computed, on a display screen having a map previously displayed thereon, comprising:

means for detecting running distance and moving direction of the running body;

means for calculating a current location from the running distance and the moving direction and obtaining a travel path;

means for extracting a linear running portion from the travel path of the running body obtained by storing and holding data of the current location thus obtained;

means for extracting a linear road portion from a predetermined area on the map which corresponds to the extracted linear running portion;

means for effecting matching between the extracted linear running portion and the extracted road portion by comparing the extracted linear running portion and the extracted road portion and determining whether a positional relationship therebetween is satisfied;

means for bringing the current location into line with the road to which the matching has been effected;

means for effecting coordinates transformation to transform the linear running portion extracted from the travel path and the linear road portion extracted from the road on the map in correspondence with said linear running portion on a first corrdinate system into points on a second coordinate system; and

means for effecting the matching between the linear running portion and the linear road portion on said second coordinate system,

wherein the coordinates transformation is effected by using Hough Transformation.

2. An apparatus for displaying a current location of a running body in which a continuously changing location of the running body on X-Y coordinates is successively computed and a current location of the running body is displayed, in accordance with data thus computed, on a display screen having a map previously displayed thereon, comprising:

means for detecting running distance and moving direction of the running body;

means for calculating a current location from the running distance and the moving direction and obtaining a travel path;

means for extracting a linear running portion from the travel path of the running body obtained by storing and holding data of the current location thus obtained;

means for extracting a linear road portion from a predetermined area on the map which corresponds to the extracted linear running portion;

means for effecting matching between the extracted linear running portion and the extracted road portion by comparing the extracted linear running portion and the extracted road portion and determining whether a positional relationship therebetween is satisfied; and

means for bringing the current location into line with the road to which the matching has been effected;

wherein the means for extracting the linear running portion includes (a) means for ascertaining if a change in running direction is substantially zero at the time when the running body has moved for a predetermined distance from an initial position, (b) means for imposing an imaginary straight line in a running direction of the running body from the initial position, (c) means for determining a distance between the current location of the running body and the imaginary straight line, and (d) means for deciding that the running body is running on a straight line on the basis that as long as the distance between the current location of the running body and the imaginary straight line is shorter than a predetermined value, the running body is running on a straight line and the linear running portion is extracted therefrom.

3. An apparatus for displaying a current location of a running body in which a continuously changing location of the running body on X-Y coordinates is successively computed and a current location of the running body is displayed, in accordance with data thus computed, on a display screen having a map previously displayed thereon, comprising:

means for detecting running distance and moving direction of the running body;

means for calculating a current location from the running distance and the moving direction and obtaining a travel path;

means for extracting a linear running portion from the travel path of the running body obtained by storing and holding data of the current location thus obtained;

means for extracting a linear road portion from a predetermined area on the map which corresponds to the extracted linear running portion;

means for effecting matching between the extracted linear running portion and the extracted road portion by comparing the extracted linear running portion and the extracted road portion and determining whether a positional relationship therebetween is satisfied; and

means for bringing the current location into line with the road to which the matching has been effected;

wherein the means for extracting the linear road portion includes (a) means for defining an area by parallel lines having a predetermined width therebetween on both sides of the linear running portion extracted from the travel path, and (b) means for determining whether a linear road portion has (i) a predetermined minimum length and (ii) a running direction which falls within a predetermined range.