Method and system for beacon/heading emergency vehicle intersection preemption

• US 7,116,245 B1
• Filed: 11/07/2003
• Issued: 10/03/2006
• Est. Priority Date: 11/08/2002
• Status: Expired due to Fees

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Bachelder, Aaron D.
• Primary Examiner(s): Mullen, Thomas
• Application Number:
  US10/704,530
• Time in Patent Office: 1,061 Days
• Field of Search: 340/906, 340/907, 340/916, 340/917, 340/919, 340/924, 340/902
• US Class Current: 340/906
• CPC Class Codes: G08G 1/087 Override of traffic control, e.g. by signal transmitted by an emergency vehicle

Abstract

An emergency vehicle intersection preemption beacon/heading system and method that relies on the use of highly localized, low-power communication system. The system can be implemented in a “car-active” mode or a “car-passive” mode. In the “car-active” mode, the system includes a low-power transmitter providing a beacon channel for all emergency vehicles that allow them to separately communicate with each intersection for a very short period of time and within very close proximity. The localized low-power transmitter continuously transmits the emergency vehicle ID and heading every second. When within range, receivers at each intersection are able to lock the signal and begin receiving ID and heading data. In the “car-passive” system, each intersection will have a low-power, highly localized transmitter. In this embodiment, the intersection constantly sends out pulses of data. Thus when an emergency vehicle with a receiver encounters an intersection signal, it records the latitude/longitude location of that intersection and waits for the signal to disappear. Information regarding the emergency vehicle is transmitted to all surrounding intersections.

Claims

1. An intersection preemption system comprising:

a first transmitter coupled to a first intersection transmitting data;

a receiver coupled to a vehicle for receiving the data from said first transmitter;

a processor in said vehicle coupled to the receiver, the processor identifying location information of the first intersection responsive to the received data;

a second transmitter coupled to the vehicle, the second transmitter forwarding vehicle heading and vehicle location information to a second intersection, the second intersection being configured to control flow of traffic at the second intersection based on the vehicle heading and vehicle location information.

2. The system according to claim 1, wherein the first transmitter is a short-range beacon transmitter and the receiver is a short-range beacon receiver.

3. The system according to claim 1, wherein said second intersection is configured to calculate the estimated time of arrival of said vehicle, and send preemption commands to a traffic light controller at said second intersection for preempting traffic lights coupled to the second intersection.

4. The system according to claim 1, wherein the second transmitter is a medium-range transceiver.

5. The system of claim 1, wherein the vehicle location information is the identified location information of the first intersection.

6. The system of claim 1, wherein the vehicle heading information includes direction information for the vehicle upon exiting the first intersection.

7. The system of claim 1, wherein the second transmitter transmits the vehicle heading and vehicle location information responsive to a lapse of communication between the first intersection and the vehicle.

8. The system of claim 1 further comprising a dead-reckoning device coupled to the vehicle for recalibrating the vehicle location information to the identified location information of the first intersection.

9. An intersection preemption method comprising:

transmitting data by a first transmitter coupled to a first intersection;

receiving by a receiver coupled to a vehicle the data transmitted by the first transmitter;

identifying location information of the first intersection responsive to the received data;

determining vehicle location based on the location information of the first intersection;

transmitting to a second intersection by a second transmitter coupled to the vehicle, vehicle heading and vehicle location information, the second intersection being configured to control flow of traffic at the second intersection based on the vehicle heading and vehicle location information.

10. The method according to claim 9, wherein said first transmitter is a short-range beacon transmitter.

11. The method according to claim 9, wherein said second transmitter is a medium-range transceiver in said vehicle.

12. The method of claim 9, wherein the determining includes recalibrating the vehicle location information to the identified location information of the first intersection.

13. The method of claim 9, wherein the vehicle heading information includes direction information for the vehicle upon exiting the first intersection.

14. The method of claim 9, wherein the second transmitter transmits the vehicle heading and vehicle location information responsive to a loss of signal between the first transmitter and the receiver.

15. An intersection preemption system comprising:

a receiver coupled to a first intersection receiving vehicle heading information transmitted by a vehicle;

a processor coupled to the receiver at the first intersection, the processor determining an outbound direction for the vehicle based on the vehicle heading information and forwarding the outbound direction and information associated with the first intersection to a second intersection, the second intersection being configured to control flow of traffic at the second intersection based on the outbound direction of the vehicle and the information associated with the first intersection.

16. The system of claim 15, wherein the processor forwards the outbound direction for the vehicle and the information associated with the first intersection responsive to a lapse of communication with the vehicle.

17. The system of claim 15, wherein the receiver receives updated vehicle heading information at periodic intervals.

18. The system of claim 17, wherein the processor accumulates a plurality of vehicle heading data points and maps the heading data points onto a local street map.

19. The system of claim 15, wherein the information associated with the first intersection includes location information of the first intersection.

20. An intersection preemption method comprising:

receiving at a first intersection, vehicle heading information transmitted by a vehicle;

determining an outbound direction for the vehicle based on the vehicle heading information; and

forwarding the outbound direction and information associated with the first intersection to a second intersection, the second intersection being configured to control flow of traffic at the second intersection based on the outbound direction of the vehicle and the information associated with of the first intersection.

21. The method of claim 20, wherein the outbound direction information and the information associated with the first intersection are forwarded responsive to a lapse of communication with the vehicle.

22. The method of claim 20, wherein the vehicle heading information is received at periodic intervals.

23. The method of claim 22 further comprising:

accumulating a plurality of vehicle heading data points; and

mapping the heading data points onto a local street map.

24. The method of claim 20, wherein the information associated with the first intersection includes location information of the first intersection.