Could Texas Intersections Add a New Traffic Light Color for Self-Driving Cars?

AUSTIN, Texas (KPEL News) - Texas drivers may someday encounter a new color at busy intersections: white. Researchers at NC State University have proposed a "white phase" traffic signal to help manage the flow of connected and autonomous vehicles (CAVs) as they become more common.

This new light would instruct human drivers to follow the car in front of them, allowing autonomous vehicles (AVs) to guide traffic, reduce delays, and lower fuel consumption.

What Is the White Light Phase?

The proposed white light phase would introduce a new type of control at intersections with a mix of AVs and traditional vehicles. Under this system:

• White light: Instructs drivers to follow the vehicle in front, with AVs coordinating the flow.
• Red light: Continues to mean stop.
• Green light: Still signals drivers to go.
• Yellow light: Remains a caution signal to prepare to stop.

During the white phase, AVs would communicate with each other and the traffic signal, acting as “mobile controllers” to help guide human drivers through the intersection. If there are too few AVs in the traffic flow, the intersection would revert to the standard red-yellow-green cycle.

How Texas Could Benefit from the White Phase

For Texas, a state known for its busy highways and major city intersections, this technology could be transformative. Researchers found that the white phase can significantly reduce traffic delays and fuel use:

• 3% reduction in travel delays with only 10% AVs on the road
• 10% reduction in travel delays when half of vehicles are autonomous
• Up to 13% reduction in fuel consumption as AV adoption grows

These efficiency gains could ease congestion on Texas roads, particularly in high-traffic areas like Houston, Dallas, and Austin.

How the White Light Phase Works

The white phase concept uses a distributed computing approach, where AVs communicate directly with each other and the intersection signal. Dr. Ali Hajbabaie, a co-developer of the white phase, describes AVs as “mobile controllers” that manage the flow of traffic through the intersection safely. Testing is already underway through simulations and controlled environments to ensure safety and effectiveness.

What Challenges Lie Ahead for Texas?

Implementing a white phase system across Texas would require a few significant steps:

1. Infrastructure Upgrades: Intersections would need AV-compatible technology, which could be costly.
2. Public Education: Texas drivers would need to learn how to respond to the white light and understand its role in traffic flow.
3. Timeframe: Widespread implementation is likely years away, depending on how quickly AV technology and infrastructure evolve.

The Future of Traffic in Texas

While the white phase concept isn’t yet ready for widespread use, researchers see practical applications in specific settings, like commercial ports and busy delivery hubs where AVs are already in use. Dr. Leila Hajibabai, a co-author, points to commercial vehicle traffic as an ideal testing ground for the white phase, as these environments often have high volumes of AV-compatible vehicles.

What’s Next for Texas Drivers?

The white light phase is still in development, but as AV technology advances, Texas could see major safety and efficiency benefits at intersections. Reduced delays, improved air quality from lower fuel consumption, and safer management of busy intersections are among the potential advantages.

Conclusion

As Texas continues to prepare for the future of AVs, the white phase could one day become an important part of the state’s traffic control systems. With the right infrastructure investments and driver education, Texas could lead the way in implementing this innovative solution, ensuring smoother, safer commutes on Texas roads.