An Austin air traffic controller successfully campaigned for a protected left turn signal at a busy intersection near the airport, making the area safer for drivers.
Practical Engineering on MSN

How Traffic Signals Really Work

Every green light, red light, and split second of timing is part of an invisible system designed to keep millions of people safe this video uncovers how engineers control chaos at intersections and ...
After a successful trial run of a system that allows devices on emergency vehicles to control traffic signals while on ...