Traffic Lights Could Get A New Colour For Autonomous Vehicles. Here's Why

All of us are aware that the traffic light colours- red, yellow (also known as amber), and green, are arranged vertically or horizontally in that order. These are the same across the globe and have been the same for over a century. Scientists have now proposed a fourth colour for these lights for driverless vehicles, as per a report in Metro UK.

There are no completely driverless cars on the road, given autonomous vehicles (AVs) are a relatively new concept. Waymo, a self-driving taxi company, has nearly reached the fifth level, or SAE4, in California and Arizona. Teslas and other AVs are growing in popularity as well. Meanwhile, self-driving cars are not currently permitted on UK roads with a few exceptions. However, the Automated Vehicles Act may allow them as early as 2026. This indicates that autonomous and human-driven vehicles will soon co-exist on the roads.

Amid this, North Carolina State University engineers are putting forth a "white light" at traffic lights, which would enable self-driving cars to assist with traffic flow and communicate with human drivers to inform them about what is happening. The goal, according to study head Dr Ali Hajbabaie, was to use the AVs' computer capability to determine which vehicles were where.

"The white phase concept incorporates a new traffic signal, so that human drivers know what they are supposed to do. 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," he said.

Dr Hajbabaie along with his team made several computer simulations to visualise how the new system, which could improve travel time, fuel efficiency and safety, would work. The findings are published in the Journal of Computer-Aided Civil and Infrastructure Engineering. According to the proposal, AVs would be able to wirelessly communicate with computers that manage traffic signals as well as with one another. When a sufficient number of autonomous vehicles approach the intersection, the new traffic signal system will activate. Any non-automated vehicles would just need to follow the vehicle in front of them, and the white light would communicate to onlookers that the AVs are coordinating their motions to move traffic through the crossing.

However, the traditional red, yellow, and green lights will be used for most of the time until practically all cars are autonomous vehicles, and the system will operate just as it has for more than a century. The team also found out that the white light concept "improves traffic efficiency for both vehicles and pedestrians."

"If at some point in the future we see almost universal adoption of AVs, our models suggest that delays at intersections would decrease by more than 25%. More realistically, we will eventually see a lower percentage of wirelessly connected AVs on the road, but there would still be meaningful improvements in traffic time," the scientist added.