A Study Proves Stoplights Need a Fourth Color: White

More electric vehicles (EVs) and autonomous vehicles (AV) are already leading engineers to implement electric roadways and city planners to design dedicated lanes for AVs—and now, the humble traffic light is next for a makeover.

For the dawning age of the self-driving car, transportation engineers from North Carolina State University are proposing the addition of a fourth “white light” whose function would be to alert humans to simply “follow the car in front of them.”

That’s because to leverage the full potential of autonomous cars means to also embrace their ability to act as a kind of hive mind. Because they’re essentially computers on wheels, these cars can network with both the traffic light and other nearby self-driving cars to help ease traffic delays and increase fuel (or electricity) efficiency. The team’s results were published in the journal IEEE Transactions on Intelligent Transportation Systems on Monday.