TRAFFIC FLOW THROUGH AN INTERSECTION BY REDUCING PLATOON INTERFERENCE

• US 20140210645A1
• Filed: 01/30/2013
• Published: 07/31/2014
• Est. Priority Date: 01/30/2013
• Status: Active Grant

• Current Assignee: Wavetronix
• Original Assignee: Wavetronix
• Inventors: Sharma, Anuj
• Granted Patent: US 9,412,271 B2
• Time in Patent Office: Days
• US Class Current: 340/907
• CPC Class Codes: G08G 1/0125 Traffic data processing
• 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
• CPC Class Codes: G08G 1/065 by counting the vehicles in a section of the road or in a parking area, i.e. comparing incoming count with outgoing count
• CPC Class Codes: G08G 1/07 Controlling traffic signals
• CPC Class Codes: G08G 1/08 according to detected number or speed of vehicles
• CPC Class Codes: G08G 1/22 Platooning, i.e. convoy of communicating vehicles

Abstract

Methods, systems, and computer program products for optimizing automobile traffic flow through an intersection by detecting and reducing platoon interference. One method, performed in a computer product, includes steps of identifying a cluster in traffic information of a cycle of a traffic signal, determining that the cluster qualifies as an upstream platoon, calculating properties of the platoon, and generating an Enhanced Purdue Coordination Diagram (EPCD) for the cycle based on the calculated properties of the platoon. Another method includes obtaining, by a computer device, traffic information corresponding to an intersection; determining, by the computer device, platoon properties of the traffic information corresponding to each cycle of a traffic signal; and calculating, by the computer device, a timing change to make to the traffic signal to improve traffic flow through the intersection, the timing change being based on the platoon properties.

Claims

1. In a computer product comprising a processor and memory, a method of improving traffic flow by analyzing traffic information corresponding to a cycle of a traffic signal, the method comprising:

identifying a cluster in the traffic information;

determining that the cluster represents a group of vehicles that qualifies as an upstream platoon;

calculating properties of the platoon based on the traffic information; and

generating an Enhanced Platoon Coordination Diagram (EPCD) for the cycle based on the calculated properties of the platoon.

2. The method recited in claim 1, further comprising:

identifying a second cluster in the traffic information; and

determining that the second cluster represents a group of vehicles that do not qualify as an upstream platoon.

3. The method recited in claim 1, wherein identifying the cluster comprises performing a Density-Based Spatial Clustering of Applications with Noise (DBSCAN) on a grid representative of the traffic information, the grid comprising entries corresponding to multiple zones of traffic for multiple time periods, wherein each cell of the grid is deemed to be occupied or unoccupied dependent on whether at least one vehicle was detected in the corresponding zone of traffic during the time represented by the cell.

4. The method recited in claim 1, wherein the cluster comprises a number of points and wherein determining that the cluster represents a group of vehicles that qualifies as an upstream platoon comprises:

determining that the number of points in the cluster is greater than or equal to a predetermined minimum number of points; and

determining that a scarcity ratio of the cluster is less than or equal to a predetermined threshold value.

5. The method recited in claim 4, wherein the scarcity ratio is the ratio of total empty spaces to total filled spaces in a time space matrix of the cluster.

6. The method recited in claim 1, wherein calculating properties of the platoon comprises:

generating a platoon velocity field based on the traffic information; and

using the platoon velocity field to determine the properties of the platoon.

7. The method of claim 1, wherein calculating properties of the platoon comprises calculating one or more of:

a duration of the platoon;

a relative start time and a relative end time of hard interference experienced by the platoon; and

a relative start time and a relative end time of soft interference experienced by the platoon.

8. The method recited in claim 1, wherein calculating properties of the platoon comprises:

determining interference experienced by the platoon; and

determining whether the interference is upper interference, lower interference, or both.

9. The method recited in claim 1, wherein generating the EPCD for the cycle comprises representing vehicles in the platoon differently than vehicles not in the platoon.

10. The method recited in claim 1, wherein generating the EPCD for the cycle comprises representing vehicles that experienced hard interference in the platoon differently than vehicles that experienced soft interference in the platoon.

11. A computer readable medium having stored thereon instructions that when executed by a processor cause the method recited in claim 1 to be performed.

12. A method of improving traffic flow, the method comprising:

obtaining, by a computer device having a processor, traffic information corresponding to an intersection having a traffic signal;

determining, by the computer device, platoon properties corresponding to each cycle of the traffic signal, based on the traffic information; and

calculating, by the computer device, a timing change to make to the traffic signal to improve traffic flow through the intersection, the timing change being based on the platoon properties.

13. The method recited in claim 12, wherein obtaining the traffic information corresponding to the intersection comprises:

selecting a desired time period; and

obtaining previously recorded traffic information corresponding to the intersection for the desired time period.

14. The method recited in claim 12, further comprising generating, by the computer device, a multi-cycle Enhanced Platoon Coordination Diagram (EPCD) based on the platoon properties.

15. The method recited in claim 12, further comprising changing the timing of the traffic signal to incorporate the calculated timing change.

16. The method recited in claim 15, further comprising:

determining an impact the changed timing of the traffic signal has on traffic flow through the intersection; and

adjusting the timing of the traffic signal to optimize the traffic flow through the intersection.

17. The method recited in claim 12, wherein determining the platoon properties comprises determining an amount of hard interference and an amount of soft interference experienced by each platoon.

18. A system comprising:

a traffic monitor that records traffic information corresponding to an approach of an intersection;

a computing device that receives the traffic information from the traffic monitor and generates an Enhanced Platoon Coordination Diagram (EPCD) based on the traffic information, the computing device comprising a processor and memory;

a user interface configured to display to the user the EPCD generated by the computing device.

19. The system recited in claim 18, wherein the computing device is configured to calculate a timing change to make to a traffic signal of the intersection to improve traffic flow through the intersection, the timing change being based on the traffic information received by the computing device.

20. The system recited in claim 18, wherein the traffic monitor comprises a traffic sensor that concurrently records traffic data corresponding to separate zones of the intersection approach.

21. The system recited in claim 20, wherein the traffic sensor concurrently records traffic data corresponding to five separate zones.

22. The system recited in claim 18, wherein the computing device comprises a server of a web site.

23. The system recited in claim 18, wherein the computing device comprises a database that stores traffic information corresponding to a plurality of intersections.

24. The system recited in claim 18, wherein the computing device comprises an analysis engine to analyze the traffic information and a reports generator to generate reports based on the traffic information corresponding to the intersection.

25. A method of improving traffic flow, the method comprising:

detecting vehicles within a traffic stream along a continuous longitudinal section of a roadway;

tracking the detected vehicles as the vehicles propagate towards a signalized intersection;

identifying clusters of vehicles within the traffic stream based upon the tracking of the vehicles;

determining which clusters belong to upstream platoons arriving at the intersection;

calculating a velocity field for each of the upstream platoons; and

determining properties of the upstream platoons based on the calculated velocity fields.

26. The method recited in claim 25, wherein tracking the detected vehicles as the vehicles propagate towards a signalized intersection comprises determining range and speed information for the vehicles as the vehicles approach the signalized intersection.

27. The method recited in claim 25, wherein the arrival of each upstream platoon at the intersection is correlated with the cycles of a traffic signal of the intersection.

28. The method recited in claim 27, further comprising generating an Enhanced Platoon Coordination Diagrams (EPCD) for each cycle of the traffic signal.

29. The method recited in claim 27, further comprising:

calculating a timing change to make to the traffic signal to improve traffic flow through the intersection, the timing change being based on the properties of the upstream platoons; and

changing the timing of the traffic signal to incorporate the calculated timing changes.