IE 11 Not Supported

For optimal browsing, we recommend Chrome, Firefox or Safari browsers.

How could adding a white traffic light improve traffic flow?

Answer: By letting AVs take over.

traffic light
Studies have shown, repeatedly, that traffic moves faster when vehicles are driverless. Their ability to communicate with each other and traffic control systems makes the whole thing go quickly and smoothly. But that’s only the case when there aren’t human drivers in the mix.

A team of scientists at North Carolina State University have developed a way to let driverless and human vehicles work together on the roadway — a fourth color at stoplights. The idea is that when the majority of cars approaching a stoplight are AVs, they will coordinate with the other driverless vehicles and the system controlling the traffic lights to determine what the best flow of traffic through the intersection would be.

The lights would then change to white, and the AVs would follow the predetermined traffic pattern, with some stopping and some proceeding through the intersection. Any human drivers in the mix would see the white light and simply follow the car in front of them. If it stops, they stop; if it keeps going, so do they. If most of the cars have human drivers, then the lights would revert to traditional colors and patterns. Computer simulations found that, if the majority of cars were AVs, this system would reduce traffic delays by more than 90 percent.