Map displaying method and apparatus, and navigation system having the map displaying apparatus

• US 20020038181A1
• Filed: 11/01/2001
• Published: 03/28/2002
• Est. Priority Date: 11/07/1996
• Status: Active Grant

• Current Assignee: Clarion Co., Ltd. (Faurecia SA)
• Original Assignee: Xanavi Informatics Corporation (Hitachi, Ltd.)
• Inventors: Endo, Yoshinori, Nakamura, Kozo, Okude, Mariko, Gunji, Yasuhiro
• Granted Patent: US 6,714,861 B2
• Time in Patent Office: Days
• US Class Current: 701/208
• CPC Class Codes: G01C 21/3635 Guidance using 3D or perspective road maps
• CPC Class Codes: G01C 21/3848 Data obtained from both position sensors and additional sensors
• CPC Class Codes: G09B 29/10 Map spot or coordinate position indicators; Map reading aids optical projection apparatus per se G03B
• CPC Class Codes: G09B 29/106 using electronic means
• CPC Class Codes: G09B 5/06 with both visual and audible presentation of the material to be studied

Abstract

The present invention is related to a stereoscopic map displaying method beneficial for a navigation system in which map information is selected from a map database according to a current location of a mobile object. The map database for storing map information comprises a plurality of types of information regarding a first map mesh provided with height information and a second map mesh with no height information wherein there is provided information for identifying that the second map mesh has no height information.

Claims

1. A map display method in which map information in an area specified in response to a current location of a moving object is read from a map database;

a perspective map looking from a view point toward a ground plane is generated by executing coordinate transformation procedures on said map information; and

a scenery image corresponding to said perspective map is displayed on a display device, wherein

said view point for generating said perspective map is established above a height of a map constituent element existing at a location specified in response to the current location of said moving object, and

said height of said view point is renewed with movement of said moving object.

2. A map display method in which map information in an area specified in response to a location indicated by an input location information is read from a map database;

a perspective map looking toward a ground plane from a view point is generated using said obtained map information; and

a scenery image corresponding to said perspective map is displayed on a display device, wherein

said map database includes information regarding heights of map constituent elements existing at least in a part of an available map area,

said view point for generating said perspective map is established above a height of a map constituent element existing at a map location specified in response to said location indicated by said input location information when information regarding height of said constituent element is available, and

said height of said view point is reset when a new input information is provided.

3. A map display apparatus connecting to a map database and a display device for displaying a map, in which map information in an area specified in response to a location indicated by an input location information is read from the map database;

a perspective map looking from a view point toward a ground plane is generated using said obtained map information;

graphic data for displaying a scenery image corresponding to said perspective map is generated; and

the graphic data is outputted to said display device, comprising

a view point setting unit for setting at least a height of said view point among variables to be set for generating said perspective map, and

a display processing unit for generating graphic data for displaying a scenery image corresponding to said perspective map generated in response to said view point established by said view point setting unit, wherein

said map database includes information regarding elevations of topographic features existing at least in a part of an available map area, and

said view point setting unit establishes a height of said view point above an elevation of a topographical feature at a map location specified in response to said location indicated by said input location information when information regarding said elevation of a topographical feature is available.

4. A map display apparatus in accordance with claim 3, wherein

said location indicated by said input location information is a current location of a moving object, and

said view point setting unit repeats its view point setting procedure when renewed location information is provided with movement of said moving object.

5. A map display apparatus in accordance with claim 4, wherein

said view point setting unit establishes said view point above in the air behind said moving object while keeping a predetermined relative relationship to a current location of the moving object, which is renewed constantly.

6. A map display apparatus in accordance with claim 4, wherein

said view point setting unit keeps the previous view point position, and reestablishes a line of sight so as to be able to capture said moving object in the current location within its field of view if a relative spatial relationship between the newly-provided current location of said moving object and the previously-established view point satisfies a predetermined condition range.

7. A map display apparatus in accordance with claim 4, wherein

said view point setting unit fixes the height of said view point when said moving object is located within a section of area which is specified in response to a predetermined range if an amount of topographic variation in an area which extends as much as said predetermined range from the current location of said moving object is not larger than a predetermined value.

8. A map display apparatus in accordance with claim 4, wherein

said moving object is an automobile, and

said view point setting unit establishes said view point for generating said perspective map looking from inside of said automobile with an elevation of a topographical feature at the current location of said automobile and a height of said automobile'"'"'s body.

9. A map display apparatus in accordance with claim 4, further comprising

input means for accepting requests from a user regarding the height of said view point to be set, wherein

said moving object is an automobile, and

said view point setting unit establishes;

said view point inside of said automobile, and a line of sight toward a moving direction of said automobile when said requested height of said view point is not larger than a predetermined value;

said view point above in the air behind said automobile, and said line of sight along a direction toward said automobile from said established view point when said requested height of said view point is within a predetermined range;

said line of sight vertically from said view point established in response to said requested height of said view point so as to view the ground plane at sea level directly below when said requested height of said view point is larger than a predetermined value.

10. A map display apparatus in accordance with claim 4, further comprising

input means for accepting requests from a user regarding a display scale to be set, wherein

said moving object is an automobile, and

said view point setting unit establishes;

said view point inside of said automobile, and a line of sight toward a moving direction of said automobile when said requested display scale is not larger than a predetermined value;

said view point above in the air behind said automobile, and said line of sight along a direction toward said automobile from said established view point when said requested display scale is within a predetermined range;

said line of sight vertically from said view point established in response to said requested height of said view point so as to view the ground plane at sea level directly below when said requested display scale is larger than a predetermined value.

11. A map display apparatus in accordance with claim 4, further comprising

input means for accepting requests regarding a view angle to be set for generating said perspective map, wherein

said display processing unit sets a value of a view angle to one of a predetermined normal value and a wide value larger than said normal value according to said accepted request, and generates graphic data for displaying said perspective map in accordance with said established view angle.

12. A map display apparatus in accordance with claim 4, further comprising

selection means for accepting requests regarding a selection of a display method between a pseudo three dimensional display method which makes it possible to give a distinctive impression of distance by executing perspective transformation procedures on two dimension horizontal data containing said map information, and a three dimensional display method which displays a scenery image using three dimensional data containing said map information, wherein

said view point setting unit establishes;

said view point at a predetermined height with respect to the ground plane at sea level when said pseudo three dimensional display method is selected, and

said view point above an elevation of a topographic feature at a map location specified in response to the current location of said moving object when said three dimensional display method is selected.

13. A map display apparatus in accordance with claim 12, wherein said view point setting unit reestablishes a height of said view point so as not to change a distance in the height direction from the ground plane to said view point when said display method is changed by said selection means between said pseudo three dimensional display method and said three dimensional display method.

14. A map display apparatus in accordance with claim 4, further comprising

decision means for deciding if information regarding the height of at least one of a topographic feature, a road, and a building is included in said obtained map information, wherein

said view point setting unit establishes said view point above an elevation of a topographic feature when said decision means decides that information regarding said elevation of a topographic feature is included in said map information, and establishes said view point at a predetermined height with respect to the ground plane at sea level when said decision means decides that information regarding said elevation of a topographic feature is not included.

15. A map display apparatus in accordance with claim 4, further comprising

decision means for deciding if information regarding the height of at least one of a topographic feature, a road, and a building is included in said obtained map information, wherein

said view point setting unit establishes said view point at a predetermined height with respect to the ground plane at sea level if a plurality of map meshes to be displayed are further included in said map information, and said decision means decides that at least one of said map meshes contains no information regarding said elevation of a topographic feature.

16. A map display apparatus in accordance with claim 4, wherein

said display processing unit generates graphic data for displaying a graphic image illustrating said moving object superposed on a scenery image to be displayed, and changes said graphic image of said moving object in response to a change of a relative spatial relationship between said established view point and said moving object due to a change in the setting condition of said view point setting unit.

18. A map display apparatus in accordance with claim 17, further comprising

a user interface for accepting requests to set at least one of a type and a height of said automobile, wherein

said map display device establishes said view point using said established variables in response to the accepted request, and generates graphic data for displaying a scenery image corresponding to said perspective map generated using said established view point.

17. A navigation system comprising a map database device for storing map information at least including information regarding topographical features and roads;

a current location detection device for detecting a current location of an automobile on which said navigation system is mounted;

a map display device for fetching map information in an area specified in response to said detected current location of said automobile, generating a perspective map viewing the ground plane from a view point using said obtained map information, and generating graphic data for displaying a scenery image corresponding said perspective map; and

a display device for displaying a map image according to said graphic data, wherein

said map display device comprises a view point setting unit for executing at least setting procedures of said view point among variables to be set for generating said perspective map, and a display processing unit for generating graphic data for displaying a scenery image corresponding to said perspective map generated in response to said view point established by said view point setting unit,

said map database includes information regarding the elevation of a topographic feature existing at least in a part of an available map area, and

said view point setting unit establishes a height of said view point above an elevation of a topographical feature at a map location which is specified in response to said detected current location of said automobile when information regarding said elevation of a topographical feature is available.

19. A map database storing map information which comprises plural types of information regarding map constituent elements, comprising at least

information regarding heights of map constituent elements existed at least in a part of an available map area, and

information for identifying the availability of said information regarding the heights.

20. A medium storing programs for realizing a map display method in which map information in an area specified in response to a location indicated by an input location information is read from a map database;

a perspective map looking from a view point toward the ground plane is generated using said obtained map information; and

a scenery image corresponding to said perspective map is displayed on a display device, wherein

said view point for generating said perspective map is established above a height of a map constituent element existing at a map location specified in response to said location indicated by said input location information when information regarding said height of said constituent element is included in said map database, and

said height of said view point is reset when new input information is provided.