Traffic light has become a vital part of road safety. Traffic management has been universally recognized in the same red, yellow (or amber) and green colors for over a century now. These colors have played an important role in guiding drivers across the world hence facilitating smooth flow of traffic with minimum accidents possible. However, with technology continually advancing and autonomous vehicles increasingly becoming common, white light could be added as the fourth color on traffic lights to enhance interaction between AVs and human drivers.
Emergence of self-driving cars
This represents a paradigm shift in transportation. While fully driverless cars are not yet widely available, the technology is developing quickly. Waymo, for instance operates in California and Arizona and its cars are almost at Level 5 autonomy according to the Society of Automotive Engineers (SAE). This means that any vehicle that meets this rating can operate without any human control under any road conditions.
Tesla among other manufacturers including Ford has made significant strides toward realizing: Autonomous Vehicle (AV) technology. The new Autonomous Vehicles Bill could open up possibilities for full autonomy by 2026 within the UK even though fully-autonomous vehicles are currently prohibited there. Could it redefine how traffic systems work?
The idea behind “white light”
Engineers from North Carolina State University propose adding “white light” into traffic signals to deal with mixed traffic conditions where autonomous and conventional cars coexist. This white light aims to increase general mobility through making better use of powerful computing resources that are found inside such autonomous cars.
The researchers head Dr Ali Hajbabaie reportedly said that this white light will act as a signal to follow the self-driving car ahead by a human driver thereby serving as an indicator for them to pause until required again before driving off under their own control. The traditional red, yellow, and green lights still retain their meanings: stop, caution, go respectively. However, when it comes to controlling intersections by self-driving cars then white light has to be used.
How does the white light system work?
The proposed system relies on autonomous vehicles ability to wirelessly communicate with other autonomous cars and traffic signal infrastructure. Once a sufficient number of self-driving cars approach an intersection, their lights turn white indicating that they are working together to manage traffic flow. Human drivers simply follow the self-driving car in front, trusting that it is optimizing traffic flow.
The concept was tested using multiple computer simulations and the results showed that white light systems can significantly improve intersection travel times, fuel efficiency and overall safety. Published in the Journal of Computer-Assisted Civil and Infrastructure Engineering, these findings indicate how traffic management could be more efficient in a future where there will be many self-driving cars.
Future of Traffic Management
However, traditional traffic lights will still be used until most vehicles on road become autonomous even if white light systems have great potential. For the time being at least, intersections will continue operating with red, yellow and green lights as they have always done for decades.
On the other hand, white light systems may become even more conspicuous as autonomous vehicles grow in popularity. Findings on the other hand from Dr. Hajbabaie’s research indicate that delays at intersections would be reduced by over 25% if nearly all vehicles were self-driven. Thus, having a small proportion of driverless autos on streets would greatly improve traffic flow.
