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Traffic signals

Fall 2019

Traffic signals: A brief history

Before automobiles even swarmed over the roads and streets, there was a need to control traffic to avoid accidents and keep vehicles moving smoothly.

The current systems have developed over more than a century, and they’re poised to change once again as vehicles become more connected and traffic control moves toward AI and complex computer-driven systems.

 

A signal history

December 10, 1868 — The first gas-lit traffic lights were installed outside the Houses of Parliament in London. Proposed by British railway engineer J.P. Knight to control the traffic of horse carriages, gas lights were manually controlled by a police officer using semaphore arms. … » More …