Traffic flow through an intersection by reducing platoon interference

• US 9,412,271 B2
• Filed: 01/30/2013
• Issued: 08/09/2016
• Est. Priority Date: 01/30/2013
• Status: Active Grant

• Current Assignee: Wavetronix
• Original Assignee: Wavetronix
• Inventors: Sharma, Anuj
• Primary Examiner(s): Girma, Fekadeselassie
• Assistant Examiner(s): BURGDORF, STEPHEN R
• Application Number:
  US13/753,869
• Publication Number:
  US 20140210645A1
• Time in Patent Office: 1,287 Days
• Field of Search: 340/907, 340/909, 340/910, 340/932, 340/934, 701/117
• US Class Current: 1/1
• 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. A computer system for monitoring traffic flow, comprising:

one or more processors; and

one or more computer-readable media having stored thereon executable instructions that when executed by the one or more processors configure the computer system to perform at least the following;

receive traffic information from one or more radar traffic sensors that are positioned along a roadway;

identify a cluster of one or more vehicles from the traffic information that was received from the one or more radar traffic sensors, wherein identifying a cluster comprises;

creating 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; and

identify the clusters using cluster identification algorithms of the occupied cells;

calculate properties of the one or more vehicles based on the traffic information received from the one or more radar traffic sensors, wherein the properties include a type of interference respectively experienced by the one or more vehicles; and

generate an Enhanced Platoon Coordination Diagram (EPCD) based on the calculated properties of the one or more vehicles, wherein the EPCD displays an arrival times of the one or more vehicles relative to a signal cycle phase and further comprises;

a set of visual distinctions within the one or more vehicles that indicate the type of interference respectively experienced by the one or more vehicles, wherein the set of visual distinctions comprises a first visual indication for each vehicle that experiences hard interference and a second, different visual indication for each vehicle that experiences soft interference.

2. The computer system recited in claim 1, wherein the executable instructions include instructions that when executed configure the computer system to:

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

3. The computer system recited in claim 1, wherein the executable instructions include instructions that when executed configure the computer system to:

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

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

determining that a density of vehicles in the cluster is greater than or equal to a predetermined minimum density;

or

determining that an extent of the cluster is greater than or equal to a predetermined minimum extent.

4. The computer system recited in claim 3, wherein the executable instructions for calculating properties of the one or more vehicles further comprise executable instructions that when executed configure the computer system to:

generate a velocity field based on the traffic information; and

use the velocity field to determine a total interference experienced within the upstream platoon or a total delay experienced traveling through an intersection.

5. The computer system of claim 3, wherein the executable instructions for calculating properties of the upstream platoon further comprise executable instructions that when executed configure the computer system to calculate:

a duration of the upstream platoon;

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

a total interference experienced within the upstream platoon or a total delay experienced traveling through an intersection; and

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

6. The computer system recited in claim 3, wherein the executable instructions for calculating properties of the upstream platoon further comprise executable instructions that when executed configure the computer system to:

determine interference experienced by the upstream platoon; and

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

7. The computer system recited in claim 3, wherein the executable instructions for generating the Enhanced Platoon Coordination Diagram further comprise executable instructions that when executed configure the computer system to represent vehicles in the upstream platoon differently than vehicles not in the upstream platoon.

8. The computer system recited in claim 1, wherein the set of visual distinctions comprises color coding.

9. The computer system recited in claim 1, wherein the set of visual distinctions comprises differences in depicted visual data points.

10. The computer system recited in claim 1, wherein the set of visual distinctions is selected from a group consisting of color coding, sizes, shapes, icons, lines, and hashing.

11. A computer-implemented method for improving traffic flow, the method comprising:

obtaining, by a computer device having a processor, traffic information corresponding to an intersection having a traffic signal, wherein the traffic information is received from a radar traffic sensor;

determining, by the computer device, platoon properties associated with a platoon, based on the traffic information received from the radar traffic sensor, wherein determining platoon properties comprises;

creating 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 by the radar traffic sensor in the corresponding zone of traffic during the time represented by the cell;

identifying clusters of occupied cells using cluster identification algorithms;

determining that the number of occupied cells in at least a portion of the grid is greater than or equal to a predetermined minimum number;

determining that the density of occupied cells in at least the portion of the grid is greater than or equal to a predetermined minimum density;

determining that the extent of the occupied cells in at least the portion of the grid is greater than or equal to a predetermined minimum extent;

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,

determining an impact that the timing change to the traffic signal has on traffic flow through the intersection; and

adjusting the timing of the traffic signal to minimize a total interference experienced within the upstream platoon or a total delay experienced traveling through an intersection.

12. The computer-implemented method recited in claim 11, 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.

13. The computer-implemented method recited in claim 11, further comprising generating an Enhanced Platoon Coordination Diagram (EPCD) that represents vehicles that experience hard interference in the platoon differently than vehicles that experience soft interference in the platoon.

14. The computer-implemented method recited in claim 11, wherein determining the platoon properties comprises determining an amount of hard interference and an amount of soft interference experienced by the platoon.

15. A system for monitoring traffic flow, comprising:

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

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

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

wherein the computing device identifies one or more clusters of vehicles from the traffic information and determines that a cluster of the one or more clusters represents a group of vehicles that qualifies as an upstream platoon by;

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

determining that a density of vehicles in the cluster is greater than or equal to a predetermined minimum density;

or

determining that an extent of the cluster is greater than or equal to a predetermined minimum extent;

wherein the EPCD comprises;

a first set of visual distinctions that distinguish individual vehicles within upstream platoons from vehicles not in the upstream platoons, wherein the first set of visual distinctions comprises displaying the individual vehicles within upstream platoons differently than at least a portion of other vehicles displayed within the EPCD.

16. The system for monitoring traffic flow recited in claim 15, 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 directed towards minimizing a total interference experienced within the upstream platoon or a total delay experienced by the upstream platoon traveling through the intersection.

17. The system for monitoring traffic flow recited in claim 15, wherein the radar traffic sensor comprises a radar sensor that concurrently records traffic data corresponding to separate zones of the intersection approach.

18. The system for monitoring traffic flow recited in claim 17, wherein the radar sensor concurrently records traffic data corresponding to nine or fewer separate zones.

19. The system for monitoring traffic flow recited in claim 15, wherein the first set of visual distinctions comprises displaying each individual upstream platoon as a separate bar.

20. The system for monitoring traffic flow recited in claim 15, wherein the computing device comprises a database that stores traffic information corresponding to a plurality of intersections.

21. The system for monitoring traffic flow recited in claim 15, 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.

22. The system for monitoring traffic flow recited in claim 15, further comprising:

a second set of visual distinctions within one or more displayed upstream platoons that indicates a type of interference experienced by one or more vehicles in the upstream platoon, wherein the second set of visual distinctions comprises different visual indications for groups of vehicles within the upstream platoon based upon the type of interference experienced by the respective groups of vehicles.

23. The system for monitoring traffic flow recited in claim 22, further comprising:

a set of visual distinctions between one or more displayed upstream platoons that indicate one or more distinct upstream platoons, wherein the set of visual distinctions comprise different visual indications for each respective platoon.

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

detecting, with a single radar traffic sensor, vehicles within a traffic stream along a continuous longitudinal section of a roadway;

tracking, with the single radar traffic sensor, 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 by;

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

determining that a density of vehicles in the cluster is greater than or equal to a predetermined minimum density;

or

determining that an extent of the cluster is greater than or equal to a predetermined minimum extent;

determining a magnitude of soft interference and hard interference experienced by one or more vehicles, wherein the magnitude of soft interference and hard interference is determined from information received from the single radar traffic sensor;

determining properties of the upstream platoons based on the determined magnitude of soft interference and hard interference;

calculating, by a computer device, a timing change to make to a traffic signal to improve traffic flow through the signalized intersection, the timing change being based on the determined magnitude of soft interference and hard interference;

changing the timing of the traffic signal to incorporate the calculated timing change;

determining an impact that the timing change to the traffic signal has on the traffic flow through the intersection; and

adjusting the timing of the traffic signal to minimize a total interference experienced with the upstream platoon or a total delay experienced traveling through an intersection.

25. The method recited in claim 24, 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.

26. The method recited in claim 24, wherein the arrival of each upstream platoon at the intersection is correlated with the cycles of a traffic signal of the intersection.

27. The method recited in claim 26, further comprising generating an Enhanced Platoon Coordination Diagrams (EPCD) for each cycle of the traffic signal.

28. The method recited in claim 24, further comprising automatically generating an array of information about one or more upstream platoons, wherein the array of information comprises a respective platoon start time, a respective platoon end time, a respective platoon length, a percentage of the respective upstream platoon that experiences hard inference, and a percentage of the respective upstream platoon that experiences soft interference.

29. The method recited in claim 24, further comprising calculating a velocity field for each of the upstream platoons.

30. A computer system for monitoring traffic flow, comprising:

one or more processors; and

one or more computer-readable media having stored thereon executable instructions that when executed by the one or more processors configure the computer system to perform at least the following;

receive traffic information from one or more radar traffic sensors that are positioned along a roadway;

identify a cluster of one or more vehicles from the traffic information that was received from the one or more radar traffic sensors;

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

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

determining that a density of vehicles in the cluster is greater than or equal to a predetermined minimum density;

or

determining that an extent of the cluster is greater than or equal to a predetermined minimum extent;

calculate properties of the one or more vehicles based on the traffic information received from the one or more radar traffic sensors to identify a type of interference respectively experienced by the one or more vehicles; and

generate an Enhanced Platoon Coordination Diagram (EPCD) based on the calculated properties of the one or more vehicles, wherein the EPCD displays the arrival times of the one or more vehicles relative to a signal cycle phase and further comprises;

a set of visual distinctions within the one or more vehicles that indicate the type of interference respectively experienced by the one or more vehicles, wherein the set of visual distinctions comprises a first visual indication for each vehicle that experiences hard interference and a second, different visual indication for each vehicle that experiences soft interference.

31. The computer system recited in claim 30, wherein the executable instructions for determining that a density of occupied cells in the cluster is greater than or equal to a predetermined minimum density further comprise executable instructions that when executed configure the computer system to determine that a scarcity ratio of the cluster is less than or equal to a predetermined threshold value.

32. The method recited in claim 31, wherein the scarcity ratio is a ratio of total empty spaces to total filled spaces in a time-space matrix of the cluster.