Probe based variable speed sign value

Patent metadata

Field	Value
Publication number	US-11069229-B2
Application number	US-201816140812-A
Country	US
Kind code	B2
Filing date	Sep 25, 2018
Priority date	Oct 8, 2014
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

Systems, methods, and apparatuses are disclosed for predicting or estimating the value of a variable speed sign (VSS). A variable speed sign is identified. Probe data is collected at one or more vehicles in proximity to the variable speed sign. The speeds of the vehicles are included in or derived from the probe data. A statistical analysis is performed on the probe data. A speed limit value for the variable speed sign is determined based on the statistical analysis.

First claim

We claim:

1. A method comprising:
receiving historical probe data collected by position circuitry from a plurality of vehicles traveling along a roadway associated with at least one variable speed sign;
map matching the historical probe data to at least one road segment;
calculating a statistical value for the historical probe data;
performing a comparison of the statistical value to one or more thresholds;
selecting a plurality of K values in response to the comparison, the plurality of K values corresponding to a plurality of bands of possible speed limits for the roadway set by the at least one variable speed sign;
receiving real time probe data for the roadway;
assigning the real time probe data to the plurality of K values;
selecting a final cluster based on an amount of the assigned real time probe data;
calculating a speed limit from the plurality of bands of possible speed limits for the roadway set by the at least one variable speed sign based on the final cluster; and
sending the speed limit to at least one approaching vehicle approaching the at least one variable speed sign, wherein a display device of the at least one approaching vehicle warns the user based on the speed limit or an engine control unit generates a command for the at least one approaching vehicle based on the speed limit.

2. The method of claim 1 , wherein the probe data includes probe data for a plurality of lanes of the roadway.

3. The method of claim 2 , wherein the plurality of lanes includes a first lane that corresponds to a first K value of the plurality of K values and a second lane that corresponds to a second K value of the plurality of K values.

4. The method of claim 1 , wherein the statistical value is a standard deviation, and the one or more thresholds include a first threshold that corresponds to a low standard deviation and a second threshold that corresponds to a high standard deviation.

5. The method of claim 1 , wherein selecting the plurality of K values comprises:
reducing a number of clusters assigned to the historical probe data; and
determining the plurality of bands of possible speed limits for the roadway based on centroids of the number of clusters assigned to the historical probe data.

6. The method of claim 1 , wherein the at least one road segment includes a plurality of road segments downstream of the at least one variable speed sign.

7. The method of claim 1 , further comprising:
selecting a plurality of initial medoid values; and
switching at least one of the initial medoid values with a non-medoid point in the historical probe data, wherein the plurality of K values corresponds to the switched medoid values.

8. The method of claim 1 , further comprising:
removing data from the historical probe data based on anomalous driving behavior detected in the historical probe data.

9. The method of claim 8 , wherein the anomalous driving behavior includes speeding vehicles, emergency vehicles, or malfunctioning vehicles.

10. The method of claim 1 , wherein the at least one variable speed sign includes a plurality of variable speed signs corresponding to different lanes of the roadway.

11. A navigation device for a vehicle, the navigation device comprising:
position circuitry configured to collect real time data for a position of the vehicle on a roadway; and
a communication interface to send the real time data for the position of the vehicle to an external device and receive from the external device a speed limit value, wherein the speed limit value is calculated from a plurality of bands of possible speed limits set by the at least one variable speed sign based on historical probe data for the roadway and assigned to a plurality of K values for the historical probe data.

12. The navigation device of claim 11 , further comprising:
a display configured to provide an alert in response to the speed limit value.

13. A non-transitory computer readable medium including instructions that when executed on a computer are operable to perform:
receiving historical probe data collected by position circuitry from a plurality of vehicles traveling along a roadway associated with a variable speed sign;
map matching the historical probe data to at least one road segment;
calculating statistical value for the historical probe data;
performing a comparison of the statistical value to one or more thresholds;
selecting a plurality of K values in response to the comparison, the plurality of K values corresponding to a plurality of bands of speed limits for the roadway set by the at least one variable speed sign;
receiving real time probe data for the roadway;
assigning the real time probe data to the plurality of K values;
selecting a final cluster based on an amount of the assigned real time probe data;
calculating a speed limit from the plurality of bands of speed limits based on the final cluster; and
sending the speed limit to at least one mobile device approaching the variable speed sign, wherein a display device of the at least one approaching vehicle warns the user based on the speed limit or an engine control unit generates a command for the at least one approaching vehicle based on the speed limit.

14. The non-transitory computer readable medium of claim 13 , wherein the probe data includes probe data for a plurality of lanes of the roadway.

15. The non-transitory computer readable medium of claim 14 , wherein a first lane of the plurality of lanes corresponds to a first K value of the plurality of K values and a second lane of the plurality of lanes corresponds to a second K value of the plurality of K values.

16. The non-transitory computer readable medium of claim 13 , wherein the statistical value is a standard deviation, and the one or more thresholds include a first threshold that corresponds to a low standard deviation and a second threshold that corresponds to a high standard deviation.

17. The non-transitory computer readable medium of claim 13 , wherein selecting the plurality of K values comprises:
reducing a number of clusters assigned to the historical probe data; and
determining the plurality of bands of speed limits for the roadway based on centroids of the number of clusters assigned to the historical probe data.

18. The non-transitory computer readable medium of claim 13 , wherein the at least one road segment includes a plurality of road segments downstream of the variable speed sign.

19. The non-transitory computer readable medium of claim 13 , the instructions when executed are operable to perform:
selecting a plurality of initial medoid values; and
switching at least one of the initial medoid values with a non-medoid point in the historical probe data,
wherein the plurality of K values corresponds to the switched medoid values.

20. The non-transitory computer readable medium of claim 13 , the instructions when executed are operable to perform:
removing data from the historical probe data based on anomalous driving behavior.

Assignees

• Here Global Bv

Inventors

• Fowe James Adeyemi
• Capota Catalin
• Stenneth Leon Oliver

Classifications

• G08G1/052

  with provision for determining speed or overspeed {(speed measuring in general G01P)} · CPC title

• G08G1/0129

  for creating historical data or processing based on historical data · CPC title

• G08G1/096775

  where the origin of the information is a central station · CPC title

• G08G1/0112 Primary

  from the vehicle, e.g. floating car data [FCD] · CPC title

• G08G1/096741

  where the source of the transmitted information selects which information to transmit to each vehicle · CPC title