Are you ready for four-color traffic lights?

Are you ready for four-color traffic lights? The first traffic light, which controlled horse traffic on the Westminster Bridge in London, consisted of semaphore flags and red and green lights. A constable manually operated it. Today, traffic lights consist of red, amber, and green lights, colors agreed upon by an international convention in 1968, and are often controlled by computers and sensors. But future traffic lights may have a fourth color: white. 

From NC State University News:

The white phase concept makes use of AVs' ability to communicate wirelessly with both each other and the computers that control the traffic signals. When enough AVs are approaching the intersection, this would activate a new traffic light – the white light. While red lights mean stop, and green lights mean go, white lights tell human drivers to simply follow the car in front of them. In short, the white light is a signal that AVs are coordinating their movement to facilitate traffic through the intersection more efficiently.

While "follow the car in front of you" sounds like a recipe for a massive pile-up, the missing piece in this puzzle is more connected autonomous vehicles and human-driven vehicles. This plan would require a large fleet of connected autonomous vehicles, new traffic signals, and likely a massive driver education campaign to be feasible. However, it could result in a vast improvement in traffic safety and reduce traffic deaths, which currently occur at a rate of over 100 deaths a day in the United States. 

Advancing the white phase mobile traffic control paradigm to consider pedestrians []