Traffic lights might see a fourth signal as self-driving cars become more practical. Getty Images/iStockphoto. The researcher’s latest plans differ from a 2020 model of a four-light intersection.

With more self-driving cars likely on the road in the not-too-distant future, traffic light technology, which hasn't changed much in the last century, may need to evolve, too.

A map of where traffic signal systems will be installed in Lenexa. (City of Lenexa) “Primarily, the locations have been selected to coincide with our pavement maintenance program,” said Schooley.

A traffic light for camels is seen at the Mingsha Mountain and Crescent Spring scenic spot on April 11, 2021 in Dunhuang, Gansu Province of China. Zhang Xiaoliang/VCG via Getty Images Chinese ...

HDOT modernized traffic signal systems at all 82 existing signalized intersections on Maui to allow connectivity between signals and to set up a cloud-based Advanced Traffic Management System (ATMS).