This Fourth Light Might Ultimately Liberate Us From Never-Ending Red Lights | Carscoops

      A recent study indicates that incorporating a fourth traffic light—white—could enable self-driving cars to handle intersections with greater efficiency.

      According to the research, human drivers would simply follow the vehicle in front of them when the white light is activated. Simulation results reveal that delays might be reduced by as much as 94 percent.

      Traffic lights, whether vertical or horizontal, have seen little change over the past century. The established colors—red for stop, yellow for caution, and green for go—remain a universal system that both facilitates urban flow and contributes to driver frustration.

      Researchers from North Carolina State University argue that it’s time for a transformative change in the U.S. transportation system, suggesting the addition of a white light.

      Their proposal, detailed in a paper published by IEEE, envisions a scenario where human drivers and autonomous vehicles share the road. The new white phase would activate only when a sufficient number of self-driving cars are at an intersection.

      In this system, connected autonomous vehicles (CAVs) would act as mobile traffic regulators. When they converge at an intersection, the white light would shine.

      This light would instruct human drivers to follow the autonomous vehicles in front. The goal would be to enhance traffic flow and decrease congestion, as these vehicles possess shared data about traffic conditions and can coordinate to optimize movement.

      The researchers describe this approach as a distributed coordination strategy, likening it to a collective intelligence for traffic management. Each connected autonomous vehicle collaborates with others to establish the most effective paths and timings, avoiding crashes and unnecessary waiting.

      When the presence of autonomous vehicles is minimal, standard red-yellow-green lights would continue to function as usual.

      “This traffic intersection concept, which we refer to as the ‘white phase,’ leverages the computing capabilities of autonomous vehicles themselves,” explains Ali Hajbabaie, the paper's lead author.

      He adds, “The white phase also introduces a new traffic signal, ensuring that human drivers understand their actions. Red signals will still indicate a stop, green signals will mean go, and white signals will guide drivers to follow the car ahead.”

      The study suggests that this method could significantly decrease traffic delays, with reductions ranging from 3.2 to 94 percent based on the number of autonomous vehicles at an intersection. Additionally, overall efficiency may improve by up to 98.9 percent compared to traditional signal timing, representing a significant time savings in a typically frustrating experience.

      However, implementing such a system is unlikely to occur in the near future. Fully autonomous vehicles are still a distant goal, and the necessary infrastructure upgrades are not yet established.

      The research notes that approximately 75 percent of existing systems would require enhancements or replacements. Ultimately, this offers a glimpse into a future where autonomous vehicles are prevalent.