Route searching device

• US 7,546,203 B2
• Filed: 01/31/2002
• Issued: 06/09/2009
• Est. Priority Date: 01/31/2001
• Status: Expired due to Fees

• Current Assignee: Clarion Co., Ltd. (Faurecia SA)
• Original Assignee: Xanavi Informatics Corporation (Hitachi, Ltd.)
• Inventors: Miyashita, Jun
• Primary Examiner(s): To; Tuan C
• Application Number:
  US10/470,849
• Publication Number:
  US 20040088109A1
• Time in Patent Office: 2,686 Days
• Field of Search: 701/200, 701/201, 701/202, 701/206, 701/210, 701/302, 701/209, 340/990, 340/995, 340/988, 340/995.2, 340/995.21, 340/995.23, 731/78.R, 342/118
• US Class Current: 701/209
• CPC Class Codes: G01C 21/34 Route searching; Route guidance

Abstract

A route searching apparatus comprises a processing device that searches a guided route along which a vehicle is to be guided from a current vehicle position to a destination and also searches a detour route for detouring a detour segment set over part of the guided route. The processing device extracts guidance-requiring intersections at which the vehicle needs to be guided to follow a course among intersections on the guided route, sets a segment ending at a guidance-requiring intersection close to the current vehicle position among the guidance-requiring intersections as the detour segment, and searches the detour route for detouring the detour segment.

Claims

1. A route searching apparatus comprising:

a processing device that includes a processor that executes a control program, stored on a computer-readable medium, to search a guided route along which a vehicle is to be guided from a current vehicle position to a destination, set a detour segment to be avoided over part of the guided route, search a detour route that avoids the detour segment, extract guidance-requiring intersections that are intersections at which the vehicle is to be guided to follow a course on the guided route and that exclude intersections at which the vehicle is not to be guided to follow a course on the guided route, and set a segment ending at a guidance-requiring intersection close to the current vehicle position among the guidance-requiring intersections as the detour segment,

wherein when a distance from the current vehicle position to the guidance-requiring intersection set as an end point of the detour segment is smaller than a predetermined lower limit, the processing device executes the control program to set a segment extending from the current vehicle position to a point on the guided route distanced from the current position by a predetermined value as the detour segment and search the detour route that avoids the detour segment thus set.

2. A route searching apparatus according to claim 1, wherein:

the processing device executes the control program to detect individual intersection types to which the guidance-requiring intersections belong based upon roadmap data, select a guidance-requiring intersection to be set as an end point of the detour segment among the guidance-requiring intersections close to the current vehicle position according to the intersection types, and search the detour route that avoids the detour segment ending at the selected guidance-requiring intersection.

3. A route searching apparatus according claim 1, wherein:

the processing device does not search the detour route when there is no intersection at which the vehicle can return to the guided route between the guidance-requiring intersection set as an end point of the detour segment and the destination.

4. A route searching apparatus according to claim 1, wherein:

the processing device does not search the detour route when an end point of the detour segment is beyond the destination.

5. The route searching apparatus of claim 1, wherein the computer-readable medium is one of a read only memory (ROM) and CD-ROM.

6. A route searching apparatus according to claim 1, wherein:

the processing device searches the detour route when an occupant on the vehicle has instructed searching a detour route.

7. A route searching apparatus comprising:

a processing device that includes a processor that executes a control program, stored on a computer-readable medium, to search a guided route along which a vehicle is to be guided from a current vehicle position to a destination, set a detour segment to be avoided over part of the guided route, search a detour route that avoids the detour segment, extract guidance-requiring intersections that are intersections at which the vehicle is to be guided to follow a course on the guided route and that exclude intersections at which the vehicle is not to be guided to follow a course on the guided route, and set a segment ending at a guidance-requiring intersection close to the current vehicle position among the guidance-requiring intersections as the detour segment,

wherein when a distance from the current vehicle position to the guidance-requiring intersection set as an end point of the detour segment exceeds a predetermined upper limit, the processing device executes the control program to set a segment extending from the current vehicle position to a point on the guided route distanced from the current vehicle position by a predetermined value as the detour segment and search the detour route that avoids the detour segment thus set.

8. A route searching apparatus comprising:

a processing device that includes a processor that executes a control program, stored on a computer-readable medium, to search a guided route along which a vehicle is to be guided from a current vehicle position to a destination, set a detour segment to be avoided over part of the guided route, search a detour route that avoids the detour segment, extract guidance-requiring intersections that are intersections at which the vehicle is to be guided to follow a course on the guided route and that exclude intersections at which the vehicle is not to be guided to follow a course on the guided route, and set a segment ending at a guidance-requiring intersection close to the current vehicle position among the guidance-requiring intersections as the detour segment,

wherein the processing device does not search the detour route when a detour start intersection at which a detour starts is not present within a predetermined distance from the current vehicle position.