As cars and trucks get smarter and more connected, the humble lights that have controlled the flow of traffic for more than a century could also be on the cusp of a major transformation.
A few years later, Detroit police officer William Potts is credited with adding the yellow light, though as a city employee he couldn't patent it. By 1930, Nelson wrote, all major American cities and many smaller ones had at least one electrical traffic signal. "When we get to the intersection, we stop if it's red and we go if it's green," said Hajbabaie, whose team used model cars small enough to hold."But if the white light is active, you just follow the vehicle in front of you."
Waymo spokesperson Sandy Karp pointed out that the self-driving car subsidiary of Google's parent company launched a fully autonomous ride-sharing service in Los Angeles and Austin, Texas, even without the addition of a fourth traffic light. Because the Michigan research deals with vehicles that have drivers, not fully autonomous ones, it could be much closer to wider implementation than what Hajbabaie is seeking.