DETECTION AND ESTIMATION OF VARIABLE SPEED SIGNS

• US 20180374346A1
• Filed: 06/23/2017
• Published: 12/27/2018
• Est. Priority Date: 06/23/2017
• Status: Active Grant

• Current Assignee: HERE Global B.V. (Nokia Corporation)
• Original Assignee: HERE Global B.V. (Nokia Corporation)
• Inventors: Fowe, James Adeyemi
• Granted Patent: US 10,553,110 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 16/287 Visualization; Browsing
• CPC Class Codes: G06F 18/23213 with fixed number of clusters, e.g. K-means clustering
• CPC Class Codes: G06V 10/763 Non-hierarchical techniques, e.g. based on statistics of modelling distributions
• CPC Class Codes: G06V 20/582 of traffic signs
• CPC Class Codes: G08G 1/0112 from the vehicle, e.g. floating car data [FCD]
• CPC Class Codes: G08G 1/0129 for creating historical data or processing based on historical data
• CPC Class Codes: G08G 1/0133 for classifying traffic situation
• CPC Class Codes: G08G 1/052 with provision for determining speed or overspeed speed measuring in general G01P
• CPC Class Codes: G08G 1/056 with provision for distinguishing direction of travel

Abstract

Systems, methods, and apparatuses are disclosed for predicting or estimating the value of a variable speed sign (VSS). Probe data is received from multiple vehicles associated with a road segment. Location values are derived from the probe data. Center distance values are calculated based on the location values and the road segment. Clusters are derived from the probe data. Center distance values are grouped according to the respective clusters and a lane is assigned to at least one cluster based on the center distance values. The speed of the cluster predicts or estimates the corresponding lane of the VSS.

Claims

1. A method comprising:

receiving probe data collected at a plurality of vehicles associated with a road segment;

determining location values for the probe data;

calculating, by a processor, center distance values for the location values based on the road segment;

determining speed values for the probe data;

performing, by the processor, an analysis on the speed values of the probe data to identify a first cluster of probe data and a second cluster of probe data;

assigning center distance values to the first cluster of probe data; and

calculating a lane assignment based on the center distance values assigned to the first cluster of probe data.

2. The method of claim 1, wherein the analysis on the speed values comprises:

identifying a first mode of the speed values; and

identifying a second mode of the speed values,

wherein the lane assignment and the first cluster of probe data are associated with the first mode of the speed values or the second mode of the speed values.

3. The method of claim 1, wherein the analysis on the speed values comprises:

detecting a number of speed limits based on a quantity of clusters including the first cluster of probe data and the second cluster of probe data.

4. The method of claim 1, wherein the analysis on the speed values comprises:

calculating a multimodal speed distribution based on the probe data.

5. The method of claim 1, further comprising:

selecting a speed value associated with the first cluster of probe data; and

providing the speed value as an estimate of a variable speed sign.

6. The method of claim 1, wherein the lane assignment assigns a speed value to a lane of the road segment.

7. The method of claim 6, wherein a warning is generated from the speed value.

8. The method of claim 6, wherein a traffic message is generated from the speed value.

9. The method of claim 6, wherein an autonomous driving command is generated from the speed value.

10. The method of claim 1, wherein the autonomous driving command includes a lane change instruction.

11. The method of claim 1, further comprising:

calculating a quantity of lanes from the analysis of speed values.

12. The method of claim 1, wherein calculating the lane assignment based on the center distance values assigned to the first cluster of probe data comprises:

assigning a left lane to the first cluster of probe data in response to center distance values having a first polarity or direction; and

assigning a right lane to the second cluster of probe data in response to center distance values having a second polarity or direction.

13. The method of claim 1, wherein calculating the lane assignment based on the center distance values assigned to the first cluster of probe data comprises:

assigning a first left lane to the first cluster of probe data in response to center distance values having an absolute value less than a threshold; and

assigning a second left lane to the second cluster of probe data in response to center distance values having an absolute value greater than the threshold.

14. An apparatus comprising:

a memory configured to store probe data collected at a plurality of vehicles associated with a road segment, wherein location values and speed values are derived from the probe data; and

a multi-modality detection and clustering device configured to calculate center distance values for the location values and analyze the speed values of the probe data to identify a cluster of probe data,

wherein a lane is assigned to a speed for the cluster of probe data based on a center distance value assigned to the cluster of probe data.

15. The apparatus of claim 14, wherein the multi-modality detection and clustering device is configured to identify a first mode of the speed values and a second mode of the speed values, wherein the lane is assigned to the first mode of the speed values for the cluster of speed data.

16. The apparatus of claim 14, wherein the multi-modality detection and clustering device is configured to determine a number of speed limits based on a quantity of clusters in the probe data.

17. The apparatus of claim 14, further comprising:

a communication device configured to send a mobile device a message, wherein the multi-modality detection and clustering device generates the message in response to the speed assigned to the lane.

18. The apparatus of claim 17, wherein the message includes a warning generated from the speed assigned to the lane or a traffic message generated from the speed assigned to the lane.

19. The apparatus of claim 17, wherein the message includes an autonomous driving command generated from the speed assigned to the lane.

20. A non-transitory computer readable medium including instructions that when executed on a computer are operable to:

collect probe data associated with a road segment; and

send the probe data to a multi-modality detection and clustering device configured to calculate center distance values for the location values and analyze the speed values of the probe data to identify a cluster of probe data, wherein a lane is assigned to a speed for the cluster of probe data based on a center distance value assigned to the cluster of probe data;

wherein a message including the speed value is broadcasted to at least one vehicle traveling near the lane.