Road estimation device and method for estimating road

• US 8,670,595 B2
• Filed: 11/22/2011
• Issued: 03/11/2014
• Est. Priority Date: 11/24/2010
• Status: Expired due to Fees

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Satoh, Taichi
• Primary Examiner(s): Koziol, Stephen R
• Assistant Examiner(s): SAINI, AMANDEEP SINGH
• Application Number:
  US13/301,822
• Publication Number:
  US 20120128214A1
• Time in Patent Office: 840 Days
• Field of Search: None
• US Class Current: 382/113
• CPC Class Codes: G01C 21/30 Map- or contour-matching
• CPC Class Codes: G01C 21/3819 Road shape data, e.g. outline of a route
• CPC Class Codes: G01C 21/3837 Data obtained from a single source
• CPC Class Codes: G01C 21/3844 Data obtained from position sensors only, e.g. from inertial navigation
• CPC Class Codes: G08G 1/091 Traffic information broadcasting broadcasting communication H04H
• CPC Class Codes: G08G 1/096716 where the received information does not generate an automatic action on the vehicle control
• CPC Class Codes: G08G 1/09675 where a selection from the received information takes place in the vehicle
• CPC Class Codes: G08G 1/096775 where the origin of the information is a central station
• CPC Class Codes: H04H 20/55 for traffic information

Abstract

A road estimation device receives data including core points assigned along a road and assigned with attributes for identifying the road. An input unit inputs map data including links in a unit of a divided region being one of divided areas. When the core points cross a boundary of an indicated divided region to be indicated, a selection unit selects a processing object core point inside the indicated divided region from the core points in the map data. An extraction unit extracts candidate links being candidate of a road represented by the processing object core point from the map data according to attributes of the links and the attribute of the processing object core point for estimating the road on a map.

Claims

1. A road estimation device configured to receive data including a plurality of core points from an external object, the core points being assigned along a road and being respectively assigned with attributes for identifying the road, the road estimation device further configured to extract links pertinent to the road represented by the core points for estimating the road on a map, the road estimation device comprising:

a map data input unit configured to input map data including links respectively having attributes corresponding to the attributes of the core points;

a link extraction unit configured to extract candidate links, which are candidate of the road represented by the core points, correspondingly to each of the core points, from the map data according to the attributes of the links and the attributes of the core points; and

a road estimation unit configured to implement a road search processing to;

extract an start-side core point and an end-side core point being adjacent to each other from an array of the core points; and

search a link pertinent to a road, which connects a start-side candidate link with an end-side candidate link, the start-side candidate link and the end-side candidate link being extracted by the link extraction unit and being respectively corresponding to the start-side core point and the end-side core point,

the road estimation unit being further configured to estimate a road on the map from the start-side core point to the end-side core point according to the searched link.

2. The road estimation device according to claim 1, wherein the road estimation unit is further configured to implement a candidate selection processing to select a candidate link being a candidate from the link, which are searched in the road search processing, according to the attribute of the core point, thereby to estimate the road on the map from the start-side core point to the end-side core point.

3. The road estimation device according to claim 2, wherein the road estimation unit is further configured to implement the candidate selection processing according to the attribute of the start-side core point among the core points.

4. The road estimation device according to claim 2, wherein the road estimation unit is further configured to select the link in the candidate selection processing according to a shape-relevant attribute among the attributes of the core point, the shape-relevant attribute being related to a road shape.

5. The road estimation device according to claim 4, wherein the road estimation unit is further configured to select the road in the candidate selection processing according to at least one of:

an attribute CA and an attribute DCA being side road information representing an angle to a side road and a connection distance to the side road;

an attribute BR and an attribute DMB being angle and distance information representing a geographical angle and a connection distance to a subsequent core point;

an attribute PD being travel distance information representing a travel distance between core points; and

an attribute PDM being spaced distance information representing a spaced distance of the road from a straight line, which connects with a subsequent core point.

6. The road estimation device according to claim 1, wherein the road estimation unit is further configured to search the link in all combinations from both termination points of the start-side candidate link to both termination points of the end-side candidate link in the road search processing.

7. The road estimation device according to claim 1, wherein the road estimation unit is further configured to search the link in the road search processing by using the end-side candidate link as the start-side candidate link when the end-side candidate link is determined by a previous processing, thereby to omit a part of road search.

8. The road estimation device according to claim 1, wherein the road estimation unit is further configured to search the link in the road search processing:

by using one termination point of the start-side candidate link as a start point when the start-side core point can be matched with one termination point of the start-side candidate link; and

by using one termination point of the end-side candidate link as an end point when the end-side core point can be matched with one termination point of the end-side candidate link,

thereby to omit a part of road search.

9. The road estimation device according to claim 1, wherein the road estimation unit is further configured to search the link from the start-side candidate link to the end-side candidate link by using a previous search result in the road search processing thereby to omit a part of road search.

10. The road estimation device according to claim 1, wherein the road estimation unit is further configured to search the link according to a direction from the start-side core point to the end-side core point in the road search processing thereby to omit a part of road search.

11. The road estimation device according to claim 1, wherein the road estimation unit is further configured to search the link according to a road classification information of the end-side candidate link of the road estimated in a previous processing in the road search processing thereby to omit a part of road search.

12. The road estimation device according to claim 1, wherein the road estimation unit is further configured to stop the road search in the road search processing,

when a travel distance from the start-side core point to the end-side core point is known as an attribute of the core point, and

when a length of the links exceeds a predetermined value, which is determined based on the travel distance, in the course of the road search.

13. The road estimation device according to claim 1, wherein the road estimation unit is further configured to stop the road search in the road search processing,

when a spaced distance of the road from a straight line, which connects the start-side core point with the end-side core point, is known as an attribute of the core point, and

when a length of the links exceeds a predetermined value, which is determined based on the spaced distance, in the course of the road search.

14. The road estimation device according to claim 1, wherein

the road estimation unit is further configured to count a value equivalent to a number of the links of the road in the course of the road search, and

the road estimation unit is further configured to stop the road search in the road search processing when the value exceeds a predetermined value in the course of the road search.

15. The road estimation device according to claim 1, wherein the road estimation unit is further configured to stop the road search in the road search processing,

when a termination point of the start-side candidate link can be matched with the start-side core point,

when a termination point of the end-side candidate link can be matched with the end-side core point, and

when a length of the links exceeds a predetermined value based on a distance between the termination points in the course of the road search.

16. The road estimation device according to claim 1, wherein in case where:

a plurality of roads, each of which includes the start-side candidate link, the link, and the end-side candidate link, exist; and

the plurality of roads has a common portion,

the road estimation unit is further configured to estimate the common portion as the road from the start-side core point to the end-side core point on the map.

17. The road estimation device according to claim 1, wherein in case where:

a plurality of roads, each of which includes the start-side candidate link, the link, and the end-side candidate link, exist;

the plurality of roads has a common portion; and

the common portion branches into a plurality of branched roads,

the road estimation unit is further configured to estimate an along-way road among the branched roads, as the road from the start-side core point to the end-side core point on the map.

18. A method for estimating a road, the method comprising:

receiving data including a plurality of core points from an external object, the core points being assigned along a road and assigned respectively with attributes for identifying the road;

inputting map data including links on a map, the links respectively having attributes corresponding to the attributes of the core points;

extracting, from the map data, candidate links, which are candidate of the road represented by the core points, correspondingly to each of the core points according to the attributes of the links and the attributes of the core points;

extracting, from an array of the core points, an start-side core point and an end-side core point being adjacent to each other;

extracting, from the candidate links, a start-side candidate link and an end-side candidate link, which respectively correspond to the start-side core point and the end-side core point;

searching a link pertinent to a road, which connects the start-side candidate link with the end-side candidate link; and

estimating, according to the searched link, a road on the map starting from the start-side core point to the end-side core point.