Navigation apparatus and navigation method

• US 5,422,815 A
• Filed: 12/14/1993
• Issued: 06/06/1995
• Est. Priority Date: 12/14/1992
• Status: Expired due to Term

• Current Assignee: Pioneer Electronics (USA) Incorporated (Pioneer Corporation)
• Original Assignee: Pioneer Electronics (USA) Incorporated (Pioneer Corporation)
• Inventors: Hijikata, Makoto
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): MCFADDEN, SUSAN IRIS
• Application Number:
  US08/165,934
• Time in Patent Office: 539 Days
• Field of Search: 364/443, 364/449, 340/990, 340/995, 73/178 R
• US Class Current: 701/208
• CPC Class Codes: G01C 21/30 Map- or contour-matching

Abstract

A navigation apparatus is provided with a measurement device for measuring a present position of a movable body, and memory device for storing map data and a map matching device. The map matching device performs map matching on the basis of the present position data and the map data to obtain a plurality of present position candidacies and select a most reliable present position candidacy as a map matched present position among the present position candidacies, and updates present position display data indicating the map matched present position. The navigation apparatus is also provided with a display unit for displaying the map matched present position on a map and for displaying a travelling locus of the movable body on the basis of a plurality of present position display data updated in the past. The navigation apparatus is further provided with a candidacy memory device for storing the present position candidacy data by each group corresponding to one travelling locus, and a travelling locus replacing device for replacing the displayed travelling locus by use of one group of the present position candidacy data.

Claims

1. A navigation apparatus comprising:

a measurement means for measuring a present position of a movable body to output present position data;

a memory means for storing map data;

a map matching means for performing map matching on the basis of the present position data and the map data to obtain a plurality of present position candidacies and selecting a most reliable present position candidacy as a map matched present position among the present position candidacies, outputting a plurality of present position candidacy data indicating the present position candidacies respectively, and updating present position display data indicating the map matched present position;

a display means for displaying a map on the basis of the map data, displaying the map matched present position on the map on the basis of the present position display data, and displaying a travelling locus of said movable body on the basis of a plurality of present position display data which have been updated in the past;

a candidacy memory means for classifying the plurality of present position candidacy data, which include the present position candidacy data corresponding to the present position candidacies not selected as the most reliable present position candidacy, into a plurality of groups each corresponding to one travelling locus, and storing the classified present position candidacy data by each group; and

a travelling locus replacing means for replacing the displayed travelling locus by use of one group of the present position candidacy data, to which the present position candidacy data corresponding to the updated present position display data belongs, if said one group is different from another group of the present position candidacy data corresponding to the present position display data used previously for displaying the travelling locus.

2. A navigation apparatus according to claim 1, wherein said measurement means comprises at least one of an earth magnetism sensor, an angular velocity sensor, a travelling distance sensor and a GPS (Global Positioning System) receiver.

3. A navigation apparatus according to claim 1, wherein said measurement means measures the present position by integrating a travelling distance of said movable body on a standard position and integrating an azimuth of said movable body on the azimuth at the standard position.

4. A navigation apparatus according to claim 1, wherein said memory means comprises a CD-ROM, to which digitized map data are stored.

5. A navigation apparatus according to claim 1, wherein said map matching means selects the most reliable present position candidacy on the basis of a drawing distance of each present position candidacy to a travelling path.

6. A navigation apparatus according to claim 1, wherein said map matching means selects the most reliable present position candidacy on the basis of a drawing angle of each present position candidacy to a travelling path.

7. A navigation apparatus comprising:

a measurement means for measuring a present position of a movable body to output present position data;

a memory means for storing map data;

a map matching means for performing map matching on the basis of the present position data and the map data to obtain a plurality of present position candidacies and for selecting a most reliable present position candidacy as a map matched present position among the present position candidacies, outputting a plurality of present position candidacy data indicating the present position candidacies respectively, and updating present position display data indicating the map matched present position;

a candidacy memory means for classifying the plurality of present position candidacy data, which include the present position candidacy data corresponding to the present position candidacies not selected as the most reliable present position candidacy, into a plurality of groups each corresponding to one travelling locus, and storing the classified present position candidacy data by each group; and

a display means for displaying a map on the basis of the map data, displaying the map matched present position on the map on the basis of the present position display data, and displaying a travelling locus of said movable body by use of one group of the present position candidacy data, to which the present position candidacy data corresponding to the present position display data currently updated by the map matching means belongs.

8. A navigation method comprising the steps of:

measuring a present position of a movable body to output present position data;

storing map data;

performing map matching on the basis of the present position data and the map data to obtain a plurality of present position candidacies and selecting a most reliable present position candidacy as a map matched present position among the present position candidacies;

outputting a plurality of present position candidacy data indicating the present position candidacies respectively;

updating present position display data indicating the map matched present position;

displaying a map on the basis of the map data, displaying the map matched present position on the map on the basis of the present position display data, and displaying a travelling locus of said movable body on the basis of a plurality of present position display data which have been updated in the past;

classifying the plurality of present position candidacy data, which include the present position candidacy data corresponding to the present position candidacies not selected as the most reliable present position candidacy, into a plurality of groups each corresponding to one travelling locus;

storing the classified present position candidacy data by each group; and

replacing the displayed travelling locus by use of one group of the present position candidacy data, to which the present position candidacy data corresponding to the updated present position display data belongs, if said one group is different from another group of the present position candidacy data corresponding to the present position display data used previously for displaying the travelling locus.