VEHICLE NAVIGATION SYSTEM WITH INTERSECTION DATABASE

• US 20100076680A1
• Filed: 09/24/2008
• Published: 03/25/2010
• Est. Priority Date: 09/24/2008
• Status: Abandoned Application

• Current Assignee: Xanavi Informatics Corporation (Hitachi, Ltd.)
• Original Assignee: Xanavi Informatics Corporation (Hitachi, Ltd.)
• Inventors: Ramaswamy, Deepak, Horiguchi, Sadanori
• Application Number:
  US12/236,814
• Publication Number:
  US 20100076680A1
• Time in Patent Office: Days
• US Class Current: 701/209
• CPC Class Codes: G01C 21/3626 Details of the output of route guidance instructions traffic control systems for road vehicles involving transmission of navigation instructions to the vehicle G08G1/0968

Abstract

A vehicle navigation system having a processor having access to a map database. An input device enters the destination to the processor and the processor, using data from the map database, calculates a preferred route to the destination. That preferred route is then displayed on a video display. The map database includes a road link database as well as an intersection database which is separate from the road link database which enables a destination to be entered to the input device by an intersection.

Claims

1. A vehicle navigation system comprising:

a processor,

a map database,

an input device for entering a destination to said processor, said processor programmed to access said map database and calculate a preferred route to said destination based upon data contained in said map database,

a video display which displays the preferred route to the destination,

wherein said map database includes a road link database and an intersection database separate from said road link database.

2. The invention as defined in claim 1 wherein said input device comprises a voice recognition circuit.

3. The invention as defined in claim 1 wherein said input device comprises a key pad.

4. The invention as defined in claim 3 wherein said key pad is displayed on said display and said display comprises a touch screen.

5. The invention as defined in claim 1 and comprising a cache memory containing intersection data from said intersection database in a predefined area surrounding a home location for the navigation system.

6. The invention as defined in claim 5 wherein said intersection data in said cache memory is stored in persistent memory.

7. The invention as defined in claim 1 and comprising a cache memory containing intersection data from said intersection database in a predefined area surrounding a current location for the navigation system.

8. The invention as defined in claim 7 wherein said processor is programmed to update the intersection data in said second cache memory whenever the location of the navigation system changes by a distance greater than a preset threshold.

9. A method for route calculation in an automotive navigation system comprising the steps of:

inputting a destination to a processor contained in the navigation system,

said processor accessing a map database and calculating a preferred route to the destination based upon information contained in said map database,

displaying the preferred route on a display device,

wherein said map database contains a road link database and an intersection database separate from said road link database.

10. The invention as defined in claim 9 wherein said inputting step comprises the step of decoding a verbal destination by utilizing a voice recognition device.

11. The invention as defined in claim 9 wherein said inputting step comprises the step of inputting the destination using a key pad.

12. The invention as defined in claim 11 wherein said key pad comprises a touch screen on said display device.

13. The invention as defined in claim 9 and comprising the step of storing intersection data for a predetermined area surrounding a home location in a cache.

14. The invention as defined in claim 13 and comprising the step of storing data in said cache in persistent memory.

15. The invention as defined in claim 9 and comprising the step of storing intersection data for a predetermined area surrounding a current location of the navigation system in a cache.

16. The invention as defined in claim 15 and comprising the step of updating the data in the cache whenever the navigation system moves more than a threshold distance.