[Not sure what happens with buses when there's transit signal priority but interesting concept. -Beth]

The Intersector: A Traffic Light That Knows When Bicycles Are Coming

It’s time for some intelligent design in our traffic management. A new device can change light times to make things safer for oncoming bikes, and more convenient for impatient drivers.

It’s a problem even in the most bike-friendly cities: cars move faster than bikes, which means cyclists are put in danger when traffic lights change. To cut down on the danger of deadly crashes, a handful of California cities, including Pleasanton, Redding, and Monterey, are installing the Intersector, a smart traffic signal that can differentiate between bikes and cars--and then times traffic light changes accordingly.

The Intersector uses a microwave radar gun that can calculate the speed and length of approaching objects, so it knows whether a bike or car is rolling up. The device then decides how long the light should stay green so that both cars and bikes have enough time to pass through. Cars get four seconds to roll through, while bikes get 14 seconds. If a cyclist pedals through a light that’s already green when they arrive, the Intersector tacks on an extra five seconds of green. If no cars are coming, it can shorten the length of a green light to let people needlessly waiting at a red go ahead sooner.

Check out a video of the Intersector in action and full story at:

http://www.fastcoexist.com/1679087/the-intersector-a-traffic-light-that-knows-when-bicycles-are-coming