According to researchers from North Carolina State University, adding a white color traffic light to traffic lights found at intersections could help to accommodate the many autonomous vehicles (AVs) on the roads. As per the proposal put forward, these white lights won’t replace the normal red, green, and yellow lights, but complement them. In the process, AVs can communicate with traffic lights to control the flow at the intersection.
What does the white traffic light at intersections signify?
Although the color white was proposed by the North Carolina State University, any other color could work just as well. The white light would serve as a signal to indicate to human drivers that autonomous vehicles are going through the intersection.
However, the traditional traffic lights will still work as per normal. According to Dr. Ali Hajbabaie, the lead researcher and associate professor of civil engineering at NC State, human drivers will still be able to drive as usual, but will also know how to maneuver their way through intersections alongside autonomous vehicles.
The inner workings of the white traffic lights
The white phase focuses on AVs approaching the intersection and provides a way for the AVs to communicate with the traffic signal and with each other. Distributed computing is key to this interaction between AVs and between AVs and the traffic lights. The white phase gets activated when the number of AVs at the intersection is rather high. At this phase, AVs will collaborate to ensure that traffic flow is well managed.
Instead of waiting for light cycles to change, AVs can move through intersections by utilizing real-time negotiation and real-time data. Human vehicles will then just have to follow the AV infront of it. When not many AVs are passing through the intersection, the system will automatically revert back to the default setting of red, yellow, and green lights. This will guarantee safety for human drivers as well.
Since AVs are able to communicate and manage traffic flow quite well, there is no longer a need to rely merely on traditional traffic light systems. The white phase will result in 3% fewer delays even when only 10% of AVs are present at an intersection.
The considerable benefit of the introduction of the white phase
The white phase has the benefit of reducing delays and ensuring that less stop-and-go traffic occurs. In the long run, fuel efficiency is ensured, as movement through intersections is much easier. At intersections with many AVs, the delays are reduced by about 94%.
Due to the new white light system, trust is ensured, and human drivers can rest assured they will be part of the well-coordinated traffic flow. A considerable benefit is that there will no longer be a gap between human drivers and AVs. There are considerable advantages to introducing the white light phase. From this year, traffic lights will have a fourth color.
Where will the implementation of the white light phase occur first?
As per North Carolina State University’s proposal, AV technology is undergoing testing, and infrastructure is already being put in place. The research team has indicated that the pilot is ready for testing, with the initial tests happening in controlled environments where the AV fleets are already in operation. The reason for choosing areas with high AV density is that these areas tend to have less pedestrian movement and serve as the perfect testing grounds for smooth traffic flow.
As stated by Hajbabaie, ports will be perfect for testing. This is because repeated traffic patterns can be seen at ports, and it has higher traffic flows. While white is ultimately the chosen traffic light color for AVs, any other color would work just as well, so the focus is not on the introduction of white traffic traffic lights, but on ensuring proper traffic control at intersections. With four color traffic lights coming to America, we have to wait and see which state will implement this new traffic light first.
