Map information supply device for mobile units

• US 7,248,965 B2
• Filed: 04/20/2004
• Issued: 07/24/2007
• Est. Priority Date: 11/10/2003
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Tanizaki, Masaaki, Shimada, Shigeru, Maruyama, Kishiko
• Primary Examiner(s): ARTHUR JEANGLAUDE, GERTRUDE
• Application Number:
  US10/827,441
• Publication Number:
  US 20050102097A1
• Time in Patent Office: 1,190 Days
• Field of Search: 701/200, 701/201, 701/207, 701/208, 701/209, 701/210, 701/211, 701/23, 701/212, 701/25, 340/990, 340/995.15
• US Class Current: 701/208
• CPC Class Codes: G01C 21/3667 Display of a road map G01C21/3614 takes precedence; guidance using 3D or perspective road maps G01C21/3635

Abstract

Disclosed is a arrangements of map information supply device for mobile units.

Claims

1. A map information device comprising:

a storage unit for map data recorded in a rectangular coordinate system based on a length at the equator where a vertical direction is a latitude and a horizontal direction is longitude;

a route search unit for searching for a route based on information on two geographical points;

an area generator unit to set an area along the route between the two geographical points by correcting a east-west width of the area by a factor based on latitude values of the routes; and

a map search unit to then search for map data for the corrected width area and to output the map data of the corrected width area.

2. A map information device according to claim 1, wherein the correcting of the width of the area based on latitude values of the routes is conducted without correcting of a height of the area.

3. A map information device according to claim 1, wherein the map data pertains to topographical features of a spherical body, and wherein the correcting of the width of the area based on latitude values is conducted to compensate for longitudinal width changes present along a latitude direction, from an equator to pole of the spherical body.

4. A map information device according to claim 3, wherein a different width correction value is applied for correcting the width, for different ranges of latitude values.

5. A map information device according to claim 1, wherein a different width correction value is applied for correcting the width, for different ranges of latitude values.

6. A map information device according to claim 1, wherein the correcting of the width of the area based on latitude values of the routes, is conducted with a correction value which is different from a value used for any correcting of a height of the area.

7. A map information device connected to a terminal, comprising:

a route search unit for searching for a route based on information for two geographical points from the terminal;

a route area predictor for predicting enroute stopping points along the route based on the information from the terminal and position information of the searched route;

an area generator unit to set a search area along the route and to expand the search area along the route in the vicinity of the predicted enroute stopping points; and

a map search unit to then search for map data for the search area, which is expanded in the vicinity of the predicted enroute stopping points, from a map database and to output the map data for the search area expanded in the vicinity of the predicted enroute stopping points.

8. A map information device according to claim 7, wherein the route area predictor establishes the enroute stopping points based on a predicted trip time schedule along the route.

9. A map information device according to claim 7, wherein the route area predictor establishes the enroute stopping points based on remaining fuel value information received from the terminal.

10. A map information device according to claim 7, wherein the route area predictor establishes the enroute stopping points based on a specified rest break time period or a continuous driving time.

11. A map information device according to claim 7 comprising:

a processor unit to simplify a line figure of the route by reducing a number of nodes consisting the route,

wherein the area generator unit sets an area along the simplified route.

12. A map information device according to claim 11:

wherein the processor omits the nodes whose distance to next nodes are equal or less than a predetermined value.

13. A map information device according to claim 8 comprising:

a processor unit to simplify a line figure of the route by reducing a number of nodes consisting the route,

wherein the area generator unit sets an area along the simplified route.

14. A map information device according to claim 7, wherein the map search unit subdivides said the expanded search area into multiple area units, and determines map data that intersects or is included in the expanded search area by subdivided area units.

15. A map information device according to claim 11, with the map data based on rectangular coordinates, wherein the area generator unit establishes the expanded search area by correcting a width of the expanded search area based on latitude values of the route.

16. A map information device according to claim 7, wherein the area generator unit extracts POI at the periphery of the predicted enroute stopping points and expands the search area along the route to include a route to the POI.

17. A map information device, comprising:

a storaqe unit for map data recorded in a rectangular coordinate system based on a length at the equator where a vertical direction is a latitude and a horizontal direction is longitude;

a route search unit for searching for a route based on information on two geographical points;

an area generator unit to set an area along the route between the two geographical points by correcting a east-west width of the area by a factor based on latitude values of the routes; and

a map search unit to then search for map data for the corrected width area and to output the map data of the corrected width area;

wherein the map search unit subdivides the area into multiple area units, and determines map data that intersects or is included in the areas by the subdivided area unit.

18. A map information device, comprising:

a storage unit for map data recorded in a rectangular coordinate system based on a length at the eguator where a vertical direction is a latitude and a horizontal direction is longitude;

a route search unit for searching for a route based on information on two geographical points;

an area generator unit to set an area along the route between the two geographical points by correcting a east-west width of the area by a factor based on latitude values of the routes; and

a map search unit to then search for map data for the corrected width area and to output the map data of the corrected width area;

with the map data based on rectangular coordinates, wherein the area generator unit establishes the area by correcting a width of the area based on latitude values of the route.