Traffic congestion degree determination device, traffic congestion degree notification device, and program

• US 20080162028A1
• Filed: 12/11/2007
• Published: 07/03/2008
• Est. Priority Date: 12/28/2006
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Satoh, Taichi
• Granted Patent: US 8,108,135 B2
• Time in Patent Office: Days
• US Class Current: 701/118
• 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

Abstract

When an average vehicle speed corresponding to a congested road section exists and at the same time, speed limit data corresponding to the congested road section is contained in map data, a degree of traffic congestion is determined based on the difference between the average vehicle speed and the speed limit. When an average vehicle speed corresponding to a congested road section exists but speed limit data corresponding to the congested road section is not contained in map data, a degree of traffic congestion is determined based on the average vehicle speed. When there is not information indicating an average vehicle speed corresponding to a congested road section, a degree of traffic congestion indicated in externally received traffic information is directly taken as the result of determination of a degree of traffic congestion.

Claims

1. A traffic congestion degree determination device comprising:

a map information acquiring unit configured to acquire map information which includes speed limit information indicating a speed limit with respect to each of some of a plurality of road sections;

a traffic information acquiring unit configured to acquire, from an external traffic information providing center, traffic information which identifies a congested road section from among the road sections and a degree of traffic congestion relative to the congested road section, wherein the traffic information further sometimes includes average speed information indicating an average vehicle speed relative to the congest road section; and

a determining unit configured to determine a degree of traffic congestion with respect to the congested road section

(i) based on the degree of traffic congestion identified by the acquired traffic information if the average speed information is not included in the acquired traffic information,

(ii) based on the average speed information if the average speed information is included in the acquired traffic information and the speed limit information is not included in the acquired map data, and

(iii) based on the average speed information and the speed limit information if the average speed information is included in the acquired traffic information and the speed limit information is included in the acquired map data.

2. The traffic congestion degree determination device according to claim 1, comprising:

a storing unit for storing a correspondence between average vehicle speeds and degrees of traffic congestion,

wherein, with respect to the congested road section, if the average speed information is included in the acquired traffic information and the speed limit information is not included in the acquired map data, the determining unit determines the degree of traffic congestion based on the correspondence between average vehicle speeds and degrees of traffic congestion stored in the storing unit.

3. The traffic congestion degree determination device according to claim 2,

wherein the map information includes road category information individually indicating road categories of the road sections,

wherein the storing unit stores the correspondence between average vehicle speeds and degrees of traffic congestion with respect to each of the road categories, and

wherein, with respect to the congested road section, if the average speed information is included in the acquired traffic information and the speed limit information is not included in the acquired map data, the determining unit determines the degree of traffic congestion based on the correspondence between average vehicle speeds and degrees of traffic congestion with respect to a road category of the congested road section.

4. A traffic congestion degree notification device comprising:

the traffic congestion degree determination device according to claim 1;

a notifying unit for notifying a user of varied information; and

a notification controlling unit for notifying the user of the degree of traffic congestion determined by the traffic congestion degree determination device through the notifying unit so that the degree of traffic congestion is recognized to correspond to the congested road section.

5. A computer readable medium including a computer program comprising instructions for causing a computer to function as the determining unit in the traffic congestion degree determination device according to claim 1.

6. A method of determining a degree of traffic congestion, the method comprising:

acquiring, from an external traffic information providing center, traffic information which identifies a congested road section from among a plurality of road sections and a degree of traffic congestion relative to the congested road section;

acquiring, if available, average speed information indicating an average speed with respect to the congested road section;

acquiring speed limit information indicating a speed limit with respect to the congested road section; and

determining a degree of traffic congestion with respect to the congested road section

(i) based on the degree of traffic congestion identified by the acquired traffic information if the average speed information is not acquired,

(ii) based on the average speed information if the average speed information is acquired and the speed limit information is not acquired, and

(iii) based on the average speed information and the speed limit information if the average speed information is acquired and the speed limit information is acquired.