Navigation device and method of use having two separate route searching devices

• US 6,662,105 B1
• Filed: 11/06/2000
• Issued: 12/09/2003
• Est. Priority Date: 11/18/1999
• Status: Expired due to Term

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Sugimoto, Hironobu, Yurimoto, Masayuki, Tada, Akihito
• Primary Examiner(s): LOUIS JACQUES, JACQUES H
• Application Number:
  US09/705,711
• Time in Patent Office: 1,128 Days
• Field of Search: 701/207, 701/208, 701/209, 701/210, 701/23, 701/213, 701/25, 701/26, 701/211, 701/214, 340/988, 340/990, 340/995, 340/995.1, 340/995.13, 340/995.19, 340/995.23, 340/995.12, 340/995.24, 731/78.R, 342/457, 342/357.13, 342/357.09
• US Class Current: 701/209
• CPC Class Codes: G01C 21/34 Route searching; Route guidance

Abstract

A route search location determining section (12d) of a mobile body (10) decides whether to conduct a route search at the mobile body (10) or to request the route search to an information center (30) based on various conditions such as priorities and how old the map data version is. In this manner, effective search can be conducted using two distinct route searching devices. Also, a current position calculating section (12a) can execute map matching by adding route data obtained from the information center (30) as a map matching candidate.

Claims

1. A navigation device mounted on a mobile body for executing route guidance, said navigation device comprising:

a mobile body route searching device for conducting a route search using a map database maintained thereon, to obtain route guiding data;

an information center route searching device for also conducting a route search to obtain route guiding data from an information center using wireless communication; and

a search selecting device that determines which device to use for obtaining route data before route search by the mobile body route searching device and obtaining route guiding data by the information center route searching device are executed, wherein the mobile body route searching device obtains initial route guiding data with no communication with the information center.

2. A device according to claim 1, wherein,

said search selecting device determines whether to use said mobile body route searching device or to use said information center route searching device according to a condition on an optimal route for the route search.

3. A device according to claim 1, wherein:

route searching is conducted for a plurality of conditions on an optimal route and said search selecting device determines a route searching device for each of said plurality of conditions.

4. A device according to claim 1, wherein,

said route searches include at least a peripheral route search for returning to a set route when off-route, in addition to a complete route search for searching routes to the destination, and said search selecting device determines the route searching device according to the type of search.

5. A device according to claim 1, wherein,

said search selecting device determines the route searching device to be used based on the version of map data in a map database maintained at said navigation device.

6. A device according to claim 1, wherein,

said search selecting device determines the route searching device to be used based on the generation date of map data in a map database maintained at said navigation device.

7. A device according to claim 1, wherein,

said search selecting device selects route searching device by dividing the route search to the destination into two sections, one near the current position and the other far from the current position.

8. A device according to claim 1, wherein,

said search selecting device determines the route searching device to be used using operation schedule information of the information center.

9. A device according to claim 1, wherein,

said search selecting device determines route search location based on a reception condition of electric waves.

10. A device according to claim 1, wherein,

said search selecting device predicts the future time period in which communication with the information center is possible, from information on areas where communication is possible and travel condition of the mobile body, and determines a route searching device to be used considering the predicted time period.

11. A device according to claim 1, wherein,

said search selecting device determines route searching device to be used considering the usage condition of the communication with the information center.

12. A device according to claim 1, wherein,

said search selecting device determines a route searching device to be used considering the past travel history of the mobile body.

13. A device according to claim 1, further comprising,

a point memory for pre-storing destination candidates, wherein,

said search selecting device selects the route searching device considering the destination candidates stored in said point memory.

14. A device according to claim 1, wherein,

said search selecting device selects a route searching device considering communications cost within a past time period having predetermined length.

15. A navigation device mounted on a mobile body for executing route guidance, said navigation device comprising:

a mobile body route searching device for conduction route search using a map database maintained thereon, to obtain route guiding data;

an information center route searching device for obtaining route guiding data from an information center using wireless communication;

a search selecting device for determining whether to use said mobile body route searching device or to use said information center route searching device; and

a display device for displaying a search result, wherein

said search selecting device selects both a mobile body route searching device and an information center route searching device and displays both search results from both devices by overlapping on the same display device.

16. A navigation device mounted on a mobile body for executing route guidance, said navigation device comprising:

a position detecting device for detecting a position of said mobile body;

a mobile body terminal for conducting a route search using a map database containing map data maintained thereon, to obtain route data;

a center route data obtaining device for also conducting a route search to obtain different route data from an information center using wireless communication, and

a map matching device for comparing said detected mobile body position and said different route data obtained from said information center to compensate for the detected position of the mobile body relative to said different route data, wherein the mobile body terminal obtains initial route guiding data with no communication with the center route data obtaining device.

17. A device according to claim 16, wherein,

said map matching device adds said route data from said information center to map matching candidates in the map data maintained at said mobile body and executes map matching.

18. A device according to claim 17, wherein,

said map matching device considers a version of the map data maintained at the mobile body terminal when judging whether to add route data obtained from the information center as a map matching candidate.

19. A device according to claim 17, wherein,

said map matching device considers the date when the map data maintained at the mobile body terminal is generated when judging whether to add route data obtained from the information center as a map matching candidate.

20. A device according to claim 17, wherein,

said map matching device decides whether to add route data obtained from the information center as a candidate based on the past travel history of the mobile body in sections where said route data and map data maintained at the mobile body terminal do not overlap.

21. A device according to claim 17, wherein,

said map matching device decides whether to add route data as a map matching candidate considering a history of travel with route data obtained.

22. A device according to claim 17, wherein,

said map matching device is capable of changing weights for roads on the map data and on route data when executing the map matching process with said route data added as a map matching candidate.

23. A navigation device mounted on a mobile body for executing route guidance, said navigation device comprising:

a position detecting device for detecting a position of said mobile body;

a mobile body terminal for conducting route search using a map database containing map data maintained thereon, to obtain route data;

a center route data obtaining device for obtaining route data from an information center using wireless communication; and

a map matching device for comparing said detected mobile body position and said route data obtained from said information center to compensate the position of the mobile body,

wherein said map matching device compares route data obtained from the information center and map data maintained at the mobile body terminal and executes map matching using only said map data maintained at the mobile body terminal when route data overlaps on a road.

24. A navigation device mounted on a mobile body for executing route guidance, said navigation device comprising:

a position detecting device for detecting a position of said mobile body;

a mobile body terminal for conducting route search using a map database containing map data maintained thereon, to obtain route data;

a center route data obtaining device for obtaining route data from an information center using wireless communication; and

a map matching device for comparing said detected mobile data position and said route data obtained from said information center to compensate the position of the mobile body,

wherein said map matching device normally executes a map matching process using map data maintained at the mobile body except when a detected position of the mobile body is off the roads on the map data, in which case route guiding data obtained from the information center is added as a map matching candidate and the map matching process is executed.

25. A navigation method for executing route guide at a mobile body, comprising the steps of:

selecting use of at least one of route guiding data obtained by conducting a mobile body route search using a map database maintained at said mobile body and route guiding data obtained by conducting a route search at an information center using wireless communication before a route search is conducted;

subsequently executing the selected route search; and

obtaining initial route guiding data by using the map database maintained at the mobile body with no communication with the information center.