Introduction of a Fourth Traffic Light Color
For over a century, traffic lights have guided us with three familiar colors: red, amber, and green. However, as we stand on the brink of an era dominated by driverless cars, this iconic trio might soon be joined by a fourth color. Scientists have proposed this change to facilitate smoother traffic flow around autonomous vehicles (AVs).
The rise of autonomous vehicles
The concept of fully autonomous vehicles is still in its nascent stages. Companies like Waymo are nearing the finalization of SAE Level 4 self-driving taxis in California and Arizona, while Tesla continues to innovate in the self-driving space. Although the UK has yet to permit self-driving vehicles on its roads, their debut is imminent with the passing of the Automated Vehicles Act.
Integration of human and driverless cars
Once the Automated Vehicles Act is enacted, our roads will witness a mix of driverless and human-steered cars. To ensure a seamless transition, engineers at North Carolina State University have proposed introducing a ‘white light’ at traffic intersections. This white light will enable self-driving cars to manage traffic flow effectively and help human drivers understand the situation around them.
The white light concept
Dr. Ali Hajbabaie, who led the study, elaborated on the concept. “The white light concept incorporates a new traffic signal so that human drivers know what they are supposed to do,” he explained. “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.”
The proposal was detailed in a paper published in the Journal of Computer-Aided Civil and Infrastructure Engineering. Dr. Hajbabaie and his team developed a series of computer simulations to test the system.
How the system works
The system relies on AVs communicating wirelessly with each other and with the computers managing the traffic signals. As AVs approach an intersection, these computers will activate the white light, signaling that the AVs are coordinating their movements through the intersection. Human drivers will be instructed to follow the vehicle ahead of them.
Benefits of the white light system
Dr. Hajbabaie emphasized the advantages of this system, including improved travel times and fuel efficiency, along with enhanced road safety. “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%,” he noted. “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 introduction of a fourth color to traffic lights marks a significant step towards integrating autonomous vehicles into our daily lives. As we prepare for this transition, innovations like the white light system will play a crucial role in ensuring our roads remain efficient and safe for all users.