Slot-Based Design Could Eliminate Traffic Lights

An MIT study determined that traffic lights, and their inefficiencies, could be eliminated if all vehicles were equipped to regulate their speed and "batch" together as they approach intersections.

1 minute read

April 12, 2016, 9:00 AM PDT

By Philip Rojc @PhilipRojc


Traffic Light

David Lofink / Flickr

Less a fully autonomous system than an extension of cruise control, the slot-based network could take away the need to wait at traffic lights. "The basic idea is that actors in a system are grouped into batches, and the speed of their movement is carefully controlled to move them more efficiently through a space."

Carlo Ratti and Paolo Santi of MIT have released a study that examines how cars could communicate to navigate intersections without coming to a stop. The system relies on sensors that relay a vehicle's trajectory to a central computer, which can then control that vehicle's speed and group it with other cars before arriving in the intersection.

Essentially, writes Kelsey Campbell-Dollaghan, "What Santi and Ratti are proposing is a super-intelligent piece of software that could take the basic model of a stoplight—cycling between stop and go—and speed it up," so that all vehicles continue through the intersections at slow but steady speeds. 

Of course, the article notes, slot-based design has to contend with the same barrier autonomous vehicles face: a human unwillingness to give up control.

Friday, March 18, 2016 in Fast Co. Design

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