https://www.engadget.com/2018/03/09/...i-truck-pilot/

Today, Waymo, which is Alphabet's self-driving company, announced a pilot program located in Atlanta to further test its autonomous technology. This time, though, the focus is on semi trucks. Beginning next week, Waymo's self-driving trucks will begin hauling cargo to Google's data centers. There will, of course, be highly trained drivers in the cabs in case anything goes awry.

To do this, Waymo is teaching its software, which has become accustomed to driving cars, how to instead manage the increased challenge of a truck. It's done in the same way you'd teach anyone with passenger car driving experience how to drive a semi.