Waymo will start testing self-driving trucks in Atlanta next week, using them to haul cargo to Google’s data centers.

Waymo — the self-driving unit of Google’s parent company, Alphabet, and a pioneer of self-driving technology — announced the test in a blog post Friday. It said each bright blue truck would have a human in the cab, ready to take control as needed. Although most of Waymo’s self-driving vehicle research uses specially built Chrysler Pacifica minivans, the company has already conducted road tests of autonomous trucks in both California and Arizona.

“Our software is learning to drive big-rigs in much the same way a human driver would after years of driving passenger cars,” the company reported. “The principles are the same, but things like braking, turning, and blind spots are different with a fully loaded truck and trailer.”

Other companies are conducting tests of robotic trucks. Uber said this week that it has been moving freight in autonomous trucks in Arizona. And San Francisco startup Starsky recently completed a 7-mile truck drive on a Florida highway, with no human aboard.