Systems and methods to detect vehicle queue lengths of vehicles stopped at a traffic light signal

• US 10,019,898 B2
• Filed: 04/05/2016
• Issued: 07/10/2018
• Est. Priority Date: 01/14/2016
• Status: Active Grant

• Current Assignee: Yunex LLC (Siemens AG)
• Original Assignee: Siemens Industry Incorporated (Siemens AG)
• Inventors: Miller, David Dodd
• Primary Examiner(s): Tran, Khoi H
• Assistant Examiner(s): Alsomiri, Majdi
• Application Number:
  US15/091,170
• Publication Number:
  US 20170206783A1
• Time in Patent Office: 826 Days
• CPC Class Codes: G08G 1/0112 from the vehicle, e.g. floating car data [FCD]
• CPC Class Codes: G08G 1/0116 from roadside infrastructure, e.g. beacons
• CPC Class Codes: G08G 1/0145 for active traffic flow control
• CPC Class Codes: G08G 1/052 with provision for determining speed or overspeed speed measuring in general G01P
• CPC Class Codes: G08G 1/08 according to detected number or speed of vehicles

Abstract

A connected traffic monitoring system comprises at least one Roadside Unit (RSU) and a traffic signal controller. The roadside unit is configured to transmit wireless signals, receive corresponding responses from a first Onboard Unit (OBU)-equipped vehicle and a second OBU-equipped vehicle and send data from the first OBU-equipped vehicle and the second OBU-equipped vehicle to the traffic signal controller. The traffic signal controller to calculate a distance between the first Onboard Unit (OBU)-equipped vehicle and the second OBU-equipped vehicle in a vehicle queue associated with a traffic light signal on an intersection, determine the queue length of the vehicle queue, determine whether the distance between the first OBU-equipped vehicle and the second OBU-equipped vehicle is greater than a vehicle length and if the distance is determined greater than the vehicle length, detect at least one non-OBU-equipped vehicle stopped in the vehicle queue behind the first OBU-equipped vehicle.

Claims

1. A method of detecting a queue length of a vehicle queue at a traffic light signal, the method comprising:

calculating a distance between a first Onboard Unit (OBU)-equipped vehicle and a second OBU-equipped vehicle in the vehicle queue associated with the traffic light signal;

determining whether the distance between the first OBU-equipped vehicle and the second OBU-equipped vehicle is greater than a vehicle length of an OBU-equipped vehicle;

if the distance is determined greater than the vehicle length, detecting at least one non-OBU-equipped vehicle stopped in the vehicle queue behind the first OBU-equipped vehicle;

determining the queue length of the vehicle queue based on the first OBU-equipped vehicle, the second OBU-equipped vehicle and an outcome of a comparison between the distance and the vehicle length to control the traffic light signal; and

transmitting wireless signals from the first OBU-equipped vehicle and the second OBU-equipped vehicle including at least one of vehicle location data, elevation data, direction heading data and speed data to a Roadside Unit (RSU).

2. The method of claim 1, further comprising:

detecting a change in the traffic light signal from a green phase to a red phase.

3. The method of claim 2, further comprising:

determining a traffic lane geometry map associated with the traffic light signal for the vehicle queue.

4. The method of claim 3, further comprising:

initiating for the traffic lane geometry map a green status by a traffic signal controller based on the queue length of the vehicle queue.

5. The method of claim 4, further comprising:

terminating the green status of the traffic lane geometry map when no vehicle presence is detected in the traffic lane geometry map.

6. The method of claim 1, further comprising:

receiving at the roadside unit (RSU) the at least one of vehicle location data, elevation data, direction heading data and speed data from the first OBU-equipped vehicle and the second OBU-equipped vehicle; and

forwarding the at least one of vehicle location data, elevation data, direction heading data and speed data from the first OBU-equipped vehicle and the second OBU-equipped vehicle to a traffic signal controller.

7. The method of claim 1, further comprising:

updating the queue length of the vehicle queue to include the at least one non-OBU-equipped vehicle.

8. The method of claim 7, further comprising:

controlling a transition from one phase to another phase of the traffic light signal based on the updated queue length of the vehicle queue.

9. The method of claim 1, further comprising:

identifying an intersection MAP and associated vehicle queues corresponding to respective traffic light signals of an intersection relating to the traffic light signal;

calculating distances between Onboard Unit (OBU)-equipped vehicles in the associated vehicle queues; and

identifying gaps between the OBU-equipped vehicles to calculate more accurate queue lengths of the associated vehicle queues.

10. A connected vehicle traffic monitoring system, the system comprising:

a traffic signal controller; and

at least one Roadside Unit (RSU) located at an intersection, the roadside unit (RSU) comprising at least a processor and a wireless transceiver, the roadside unit (RSU) configured to transmit wireless signals and receive corresponding responses from a corresponding wireless device of a first Onboard Unit (OBU)-equipped vehicle and a second OBU-equipped vehicle, and to send at least one of vehicle location data, elevation data, direction heading data and speed data from the first OBU-equipped vehicle and the second OBU-equipped vehicle to the traffic signal controller,

wherein the traffic signal controller to;

calculate a distance between the first Onboard Unit (OBU)-equipped vehicle and the second OBU-equipped vehicle in a vehicle queue associated with a traffic light signal on the intersection;

determine the queue length of the vehicle queue based on the first OBU-equipped vehicle and the second OBU-equipped vehicle;

determine whether the distance between the first OBU-equipped vehicle and the second OBU-equipped vehicle is greater than a vehicle length of an OBU-equipped vehicle; and

if the distance is determined greater than the vehicle length, detect at least one non-OBU-equipped vehicle stopped in the vehicle queue behind the first OBU-equipped vehicle.

11. The system of claim 10, wherein the traffic signal controller to:

detect a change in the traffic light signal from a green phase to a red phase.

12. The system of claim 11, wherein the traffic signal controller to:

determine a traffic lane geometry map associated with the traffic light signal for the vehicle queue;

initiate for the traffic lane geometry map a green status by a traffic signal controller based on the queue length of the vehicle queue; and

terminate the green status of the traffic lane geometry map when no vehicle presence is detected in the traffic lane geometry map.

13. The system of claim 10, wherein the first OBU-equipped vehicle and the second OBU-equipped vehicle to transmit wireless signals including at least one of vehicle location data, direction heading data and speed data to a Roadside Unit (RSU).

14. The system of claim 13, wherein the roadside unit (RSU) device to receive the at least one of vehicle location data, direction heading data and speed data from the first OBU-equipped vehicle and the second OBU-equipped vehicle and forward the at least one of vehicle location data, direction heading data and speed data from the first OBU-equipped vehicle and the second OBU-equipped vehicle to the traffic signal controller.

15. The system of claim 10, wherein the traffic signal controller to:

update the queue length of the vehicle queue to include the at least one non-OBU-equipped vehicle; and

control a transition from one phase to another phase of the traffic light signal based on the updated queue length of the vehicle queue.