Could our conventional traffic lights of red, yellow, and green be getting a futuristic upgrade due to autonomous vehicles (AVs) on the roads? According to researchers at North Carolina State University, a fourth traffic light color could be added as a way to help AV drivers handle intersections efficiently. As part of the new idea put forward, the “white phase” could possibly assist with traffic management. Experts mentioned that the adoption of the four-color traffic lights will occur first in states surrounding ports and commercial hubs.
Understanding the “white phase”
The “white phase” signals a new color on the traffic light but allows for ease of operation at intersections. With many autonomous vehicles arriving at intersections, the “white phase” will enable all AVs to communicate with each other and with the traffic signal system. The added white light on common traffic lights will be used to signify the fact that AVs are taking control of the traffic temporarily.
Human drivers will also benefit from the “white phase”, as they will not need to decide for themselves what move to make at the intersection. They will simply resort to following the vehicle in front of them. In following autonomous vehicles, human drivers will be able to maneuver their way through an intersection more easily.
How will the addition of a white light affect traditional traffic lights?
Confusion arises because citizens feel normal traffic lights will no longer function in the same way. Traffic lights will perform in the same way as they have always functioned. Dr. Hajbabaie, associate professor of civil engineering at NC State and a co-author of the study, states,” Red lights will still mean stop. Green lights will still mean go. And white lights will tell human drivers to simply follow the car in front of them.”
When there are no AVs arriving at the traffic lights, the traditional red-yellow-green traffic light system will continue to control the situation.
The impact of the “white phase” on American roads
The introduction of the “white phase” is aimed at bettering traffic flow, cutting down on fuel consumption, and allowing for far fewer delays at intersections. Currently, delays at traffic lights are one of the biggest problems on U.S. roads, and many citizens are troubled because of traffic jams.
By using computer simulations of these advanced traffic models, researchers realized:
- Delays dropped by 70% when 30% of AVs were present.
- Traffic flowed smoothly at intersections when 70% of AVs were present, reducing delays by 99%.
- Traffic delays were considerably reduced even with a 10% AV presence.
Without stop-and-go, fuel being burned declines too, making the “white phase” a greater move towards a greener environment as well.
The current 2020 model has shown drastic improvement in comparison to the older models. This latest design by Dr. Hajbabaie and his team moves away from centralized computing and makes use of distributed computing.
Testing of the “white phase”
While this futuristic traffic light is not ready for nationwide rollout, researchers believe that the project will soon be launched. North Carolina is the first state to accept a proposal like this. However, it is believed that states with high AV traffic, like Florida, Texas, and California, will be the first to test the “white phase”. More of these traffic lights will be placed around industrial areas and ports.
More accurate data on the real-world performance of the “white phase” will be shown from these areas. It becomes imperative to keep up with the times and evolve traffic systems since AVs are on our roads. Very soon, Americans could be seeing white lights flashing at intersections.
To see the full conclusions, you can check the full study: R. Niroumand, L. Hajibabai, and A. Hajbabaie, White Phase Intersection Control Through Distributed Coordination: A Mobile Controller Paradigm in a Mixed Traffic Stream, in IEEE Transactions on Intelligent Transportation Systems, vol. 24, no. 3, pp. 2993-3007, March 2023, doi: 10.1109/TITS.2022.3226557.
