System and Method for Traffic-Control Phase Change Warnings

• US 20120026014A1
• Filed: 08/02/2010
• Published: 02/02/2012
• Est. Priority Date: 08/02/2010
• Status: Active Grant

• Current Assignee: Siemens Mobility, Inc. (Siemens AG)
• Original Assignee: Siemens Industry Incorporated (Siemens AG)
• Inventors: Miller, David Dodd, Clark, Mark Allen
• Granted Patent: US 9,013,325 B2
• Time in Patent Office: Days
• US Class Current: 340/929
• CPC Class Codes: G08G 1/07 Controlling traffic signals

Abstract

A roadside equipment (RSE) system that can be used for controlling traffic signals and other equipment and corresponding method. A method includes maintaining a traffic signal in a GREEN phase in a first direction, including displaying a GREEN indicator in the first direction. The method includes detecting an event indicating that the phase of the traffic signal in the first direction should be changed and changing the phase of the traffic signal to a pre-YELLOW phase in response to the detected event, including continuing to display the GREEN indicator in the first direction. The method includes wirelessly transmitting a message indicating the pre-YELLOW phase and a phase time, the phase time indicating a next change of phase of the traffic signal, and changing the phase of the traffic signal to a YELLOW phase when the phase time has been reached.

Claims

1. A method for controlling traffic signals, comprising:

maintaining a traffic signal in a GREEN phase in a first direction, including displaying a GREEN indicator in the first direction;

detecting an event indicating that the phase of the traffic signal in the first direction should be changed;

changing the phase of the traffic signal to a pre-YELLOW phase in response to the detected event, including continuing to display the GREEN indicator in the first direction;

wirelessly transmitting a message indicating the pre-YELLOW phase and a phase time, the phase time indicating a next change of phase of the traffic signal; and

changing the phase of the traffic signal to a YELLOW phase when the phase time has been reached.

2. The method of claim 1, wherein the transmitted message is received by a vehicle, and the vehicle displays an indication to a driver of the next change of phase.

3. The method of claim 1, wherein GREEN indicator is displayed for at least a predetermined minimum GREEN time, when the GREEN phase and pre-YELLOW phase are combined.

4. The method of claim 1, wherein the detected event includes detection of a vehicle on a cross street.

5. The method of claim 1, wherein the detected even includes a pedestrian crossing request.

6. The method of claim 1, wherein a message is also wirelessly transmitted during YELLOW phase indicating the YELLOW phase and a phase time.

7. The method of claim 1, wherein the traffic signal changes to a RED phase after the YELLOW phase, and a message is also wirelessly transmitted during RED phase indicating the RED phase and a phase time.

8. The method of claim 1, wherein the message is wirelessly transmitted in substantially only the first direction.

9. The method of claim 1, wherein the message includes a vehicle identifier corresponding to a vehicle approaching the in the first direction.

10. The method of claim 1, wherein the message includes a timestamp.

11. The method of claim 1, wherein the transmitted phase time corresponds to a global positioning system time so that the change of phase is synchronized with an indication displayed to a driver of a vehicle, the indication based on the message and the global positioning system time.

12. A roadside equipment (RSE) system comprising at least a processor and a wireless receiver, the RSE system configured to perform the steps of:

maintaining a traffic signal in a GREEN phase in a first direction, including displaying a GREEN indicator in the first direction;

detecting an event indicating that the phase of the traffic signal in the first direction should be changed;

changing the phase of the traffic signal to a pre-YELLOW phase in response to the detected event, including continuing to display the GREEN indicator in the first direction;

wirelessly transmitting a message indicating the pre-YELLOW phase and a phase time, the phase time indicating a next change of phase of the traffic signal; and

changing the phase of the traffic signal to a YELLOW phase when the phase time has been reached.

13. The RSE system of claim 12, wherein the transmitted message is received by a vehicle, and the vehicle displays an indication to a driver of the next change of phase.

14. The RSE system of claim 12, wherein GREEN indicator is displayed for at least a predetermined minimum GREEN time, when the GREEN phase and pre-YELLOW phase are combined.

15. The RSE system of claim 12, wherein the detected event includes detection of a vehicle on a cross street.

16. The RSE system of claim 12, wherein the detected even includes a pedestrian crossing request.

17. The RSE system of claim 12, wherein a message is also wirelessly transmitted during YELLOW phase indicating the YELLOW phase and a phase time.

18. The RSE system of claim 12, wherein the traffic signal changes to a RED phase after the YELLOW phase, and a message is also wirelessly transmitted during RED phase indicating the RED phase and a phase time.

19. The RSE system of claim 12, wherein the message is wirelessly transmitted in substantially only the first direction.

20. The RSE system of claim 12, wherein the message includes a vehicle identifier corresponding to a vehicle approaching the in the first direction.

21. The RSE system of claim 12, wherein the message includes a timestamp.

22. The RSE system of claim 12, wherein the transmitted phase time corresponds to a global positioning system time so that the change of phase is synchronized with an indication displayed to a driver of a vehicle, the indication based on the message and the global positioning system time.