Traffic information generating method, traffic information generating apparatus, display, navigation system, and electronic control unit

• US 8,744,735 B2
• Filed: 07/10/2007
• Issued: 06/03/2014
• Est. Priority Date: 07/10/2006
• Status: Expired due to Fees

• Current Assignee: Aisin AW Company Limited (Aisin Corp.), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Aisin AW Company Limited (Aisin Corp.), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Inoguchi, Toshio, Zaitsu, Tomoyuki, Yamada, Shinichi, Yoshikawa, Kazutaka
• Primary Examiner(s): SHAPIRO, JEFFREY ALAN
• Application Number:
  US12/307,968
• Publication Number:
  US 20090292456A1
• Time in Patent Office: 2,520 Days
• Field of Search: 701117-119, 340/995.13, 340933-943, 340988-996
• US Class Current: 701/118
• CPC Class Codes: G08G 1/0112 from the vehicle, e.g. floating car data [FCD]
• CPC Class Codes: G08G 1/0133 for classifying traffic situation
• CPC Class Codes: G08G 1/0969 having a display in the form of a map
• CPC Class Codes: G09B 29/007 using computer methods

Abstract

An embodiment provides a traffic information generating method for generating traffic information about a road on which a vehicle travels. A vehicle speed is detected by a vehicle speed sensor at predetermined distance or time intervals. By referring to a prescribed speed, a prescribed distance, and a link determination distance, a congestion degree associated with the vehicle speed is detected.

Claims

1. A traffic information generating method for generating traffic information about a road on which a vehicle travels, the method comprising:

a vehicle speed detecting step of detecting a vehicle speed of the vehicle at predetermined distance or time intervals using a vehicle speed sensor; and

a congestion degree detecting step of a congestion degree detection unit detecting a congestion degree associated with the vehicle speed by referring to a prescribed speed and a prescribed distance that are predetermined in association with the congestion degree, and a link determination distance prescribed in accordance with a road type,

wherein the congestion degree detecting step includes determining that the vehicle speed is lower than the prescribed speed between a first point at which the vehicle speed becomes equal to or greater than the prescribed speed to a second point that is within the link determination distance from the first point, when;

a) the vehicle speed is lower than the prescribed speed at the second point,

the congestion degree detecting step determining that the vehicle speed is equal to or greater than the prescribed speed between a first point at which the vehicle speed drops below the prescribed speed and a second point that is within the link determination distance from the first point when;

b) the vehicle speed is equal to or greater than the prescribed speed at the second point, and

wherein the congestion degree detecting step includes determining that the vehicle speed is not lower than the prescribed speed between the first point and the second point when the condition a) is satisfied, or that the vehicle speed is not equal to or greater than the prescribed speed between the first point and the second point when the condition b) is satisfied, in a case where the vehicle makes a right turn or a left turn between the first point and the second point.

2. The traffic information generating method according to claim 1, wherein the congestion degree detecting step includes detecting the congestion degree indicating a congestion when the vehicle speed is below the prescribed speed continuously for a distance equal to or greater than the prescribed distance,

the congestion degree detecting step detecting the congestion degree indicating a high-speed road when the vehicle speed is equal to or greater than the prescribed speed continuously for a distance equal to or greater than the prescribed distance.

3. The traffic information generating method according to claim 1, wherein the congestion degree detecting step includes a continuing step of invalidating the congestion degree that is linked in accordance with the link determination distance when the linked congestion degree does not continue for a distance equal to or greater than the prescribed distance.

4. The traffic information generating method according to claim 1, wherein the prescribed distance and the link determination distance are prescribed in accordance with the road type,

wherein the prescribed distance and the link determination distance are changed in accordance with a road type ratio at a point where the vehicle travels from one road type to another.

5. The traffic information generating method according to claim 1, further comprising an allocating step of an allocating unit extracting a link from a road map storing unit in which a road map of the road is stored, the allocating unit allocating the congestion degree linked in accordance with the link determination distance to the link.

6. The traffic information generating method according to claim 5, further comprising the steps of:

the allocating unit generating a partial congestion degree, wherein a plurality of the congestion degrees are allocated to a link having a length equal to or greater than a particular partial congestion degree generating link length; and

a link end correcting unit referring to a prescribed link end correction range and correcting the congestion degree up to the link terminal end or the link beginning end when the partial congestion degree is allocated more towards the link terminal end or the link beginning end than the link end correction range.

7. The traffic information generating method according to claim 1, wherein the congestion degree has plural levels associated with a plurality of the prescribed speeds.

8. The traffic information generating method according to claim 1, comprising generating the traffic information using an on-board device mounted on the vehicle.

9. The traffic information generating method according to claim 6, comprising:

connecting the vehicle with a vehicle information server via a network;

transmitting the vehicle information from the vehicle to the vehicle information server via the network; and

generating the traffic information using the vehicle information server.

10. The traffic information generating method according to claim 9, comprising the steps performed by the link end correcting unit of:

receiving the vehicle information from a plurality of vehicles;

grouping the partial congestion degrees of the plural vehicles with regard to the same link; and

calculating the congestion degree in terms of a statistical value of the partial congestion degrees in each group.

11. The traffic information generating method according to claim 10, wherein the partial congestion degree shared by a number of vehicles less than a predetermined number is not grouped.

12. The traffic information generating method according to claim 10, wherein, when there is a plurality of the groups, the group having a greater number of vehicles is preferentially adopted.

13. The traffic information generating method according to claim 12, wherein, when there are two or more groups that have the same number of vehicles, a longest group is preferentially adopted.

18. The traffic information generating method according to claim 1, wherein the link determination distance is set in association with the congestion degree in the road type.

14. A traffic information generating apparatus for generating traffic information about a road on which a vehicle travels, the apparatus comprising:

a congestion degree detection unit configured to detect a congestion degree in accordance with a vehicle speed that is detected by an on-board vehicle speed sensor at predetermined distance or time intervals, by referring to a prescribed speed and a prescribed distance that are predetermined in association with the congestion degree, and a link determination distance prescribed in accordance with a road type,

wherein the congestion degree detection unit is configured to determine that the vehicle speed is lower than the prescribed speed between a first point at which the vehicle speed becomes equal to or greater than the prescribed speed to a second point that is within the link determination distance from the first point, when;

a) the vehicle speed is lower than the prescribed speed at the second point,

the congestion degree detection unit is configured to determine that the vehicle speed is equal to or greater than the prescribed speed between a first point at which the vehicle speed drops below the prescribed speed and a second point that is within the link determination distance from the first point when;

b) the vehicle speed is equal to or greater than the prescribed speed at the second point, and

wherein the congestion degree detection unit is configured to determine that the vehicle speed is not lower than the prescribed speed between the first point and the second point when the condition a) is satisfied, or that the vehicle speed is not equal to or greater than the prescribed speed between the first point and the second point when the condition b) is satisfied, in a case where the vehicle makes a right turn or a left turn between the first point and the second point.

15. A display unit configured to display the traffic information generated by the traffic information generating apparatus according to claim 14.

16. A navigation system comprising:

a map data storing unit configured to store a road map of a road on which a vehicle travels;

a positioning unit configured to determine a position of the vehicle using a radio wave emitted by an artificial satellite; and

a display unit configured to display the traffic information generated by the traffic information generating apparatus according to claim 14, together with the road map.

17. An electronic control unit for generating traffic information about a road on which a vehicle travels, comprising:

a congestion degree detection unit configured to detect a congestion degree in accordance with a vehicle speed detected by a vehicle speed sensor at predetermined distance or time intervals, by referring to a prescribed speed and a prescribed distance that are prescribed in association with the congestion degree, and a link determination distance prescribed in association with a road type,

wherein the congestion degree detection unit is configured to determine that the vehicle speed is lower than the prescribed speed between a first point at which the vehicle speed becomes equal to or greater than the prescribed speed to a second point that is within the link determination distance from the first point, when;

a) the vehicle speed is lower than the prescribed speed at the second point,

the congestion degree detection unit is configured to determine that the vehicle speed is equal to or greater than the prescribed speed between a first point at which the vehicle speed drops below the prescribed speed and a second point that is within the link determination distance from the first point when;

b) the vehicle speed is equal to or greater than the prescribed speed at the second point, and

wherein the congestion degree detection unit is configured to determine that the vehicle speed is not lower than the prescribed speed between the first point and the second point when the condition a) is satisfied, or that the vehicle speed is not equal to or greater than the prescribed speed between the first point and the second point when the condition b) is satisfied, in a case where the vehicle makes a right turn or a left turn between the first point and the second point.