January 12, 2016 by Canadian Underwriter
Ford and the University of Michigan said on Monday that they have conducted what they believe are the first tests of autonomous vehicles in wintry conditions.
The automaker and university tested the vehicles in Michigan and on the university’s 32-acre Mcity simulated urban environment, noting in a statement that typical autonomous vehicle sensors are useless on snow-covered roads. University of Michigan’s (U-M) Edwin Olson, an associate professor of computer science and engineering and Ryan Eustice, an associate professor of naval architecture and marine engineering as well as electrical engineering and computer science, are the U-M researchers leading the effort with Ford.
“It’s one thing for a car to drive itself in perfect weather. It’s quite another to do the same thing when its sensors cannot sense the road through snow, or when visibility is limited by falling precipitation,” said Jim McBride, Ford’s technical leader for autonomous vehicles, in the statement from Ford. “In Ford’s home state of Michigan, we know weather isn’t always perfect. That’s why we’re conducting testing – for the roughly 70% of U.S. residents who live in snowy regions.”
The tests could easily apply to Canadian winters as well. The U-M noted that one of keys to safe autonomous driving is for a vehicle to know where it is, not just along a road, but within a driving lane. Even being off by a few inches can make a big difference, the release said, noting that under sunny skies, Ford’s testbed autonomous Fusion Hybrid sedans rely on LiDAR sensors that can pinpoint lane location with “centimetre accuracy.” LiDAR emits short pulses of laser light to precisely allow the vehicle to create a real-time, high-definition 3D image of what’s around it.
However, LiDAR cannot see the road when snow obstructs it from view – like during inclement weather or in high-density traffic, according to the Ford statement. The same is true when the sensor lens is covered by grime or debris.
The solution Ford and U-M are working on involves high-resolution 3D maps – complete with information about the road and what’s above it, including road markings, signs, geography, landmarks and topography. U-M researchers have developed these maps and Ford’s test vehicles are equipped with them. “The maps we create contain useful information about the 3D environment around the car, allowing it to localize even with a blanket of snow covering the ground,” Eustice said.
“The vehicle’s normal safety systems, like electronic stability control and traction control, which often are used on slippery winter roads, worked perfectly alongside the autonomous driving software,” McBride reported. “We eventually want our autonomous vehicles to detect deteriorating conditions, decide whether it’s safe to keep driving, and if so, for how long.”