ROCHESTER — With a clang worthy of a San Francisco cable car, the Med City Mover autonomous shuttle sidled up in front of the Mayo Clinic's Gonda Building and its doors slid open. Two women stood there, hesitating.
"Can we get in?" they asked.
They're among a trickle of passengers who have climbed aboard the driverless Med City Mover, a six-person electric-powered vehicle launched with fanfare last September in a project led by the Minnesota Department of Transportation (MnDOT). Two shuttles are serving as a movable experiment, providing free rides along a 15-block loop through downtown seven days a week.
While the Med City Mover only draws about 10 passengers a day, the state has already learned some lessons about autonomous vehicles, especially how they operate in Minnesota's storied climate.
The sensors on the vehicles are so finely tuned that at first, they slowed down or stopped entirely when they mistook snowflakes, leaves and high winds for collision hazards, said Tara Olds, deputy director of MnDOT's Connected and Automated Vehicles office. On colder days, moisture from other vehicles' exhaust at stop lights and intersections was detected as an object, as well.
MnDOT has worked on upgrades with EasyMile, the Mover's French manufacturer, "so it has a better ability to filter out those things," Olds said.
Broadly speaking, autonomous technology "needs to be further refined, developed and proven to operate in this glorious weather we have here in Minnesota," said Frank Douma, a researcher at the University of Minnesota's Center for Transportation Studies.
"Demonstrations are important because the technology needs to continue to mature," Douma added, "but we need to get them out of California, Arizona and Texas and operate in place where there's a wider variety of weather."