New research would make clearing Iowa roads safer in a blizzard

New research and technology could help guide Iowa snowplow drivers during white-out conditions and alert them to obstacles, improving driver safety and keeping roads open in low-visibility conditions.

The Iowa Department of Transportation is working with Iowa State University’s Institute for Transportation to develop a system that allows its workers to “see” better in bad weather. It entails equipping snow plows with sensors and driver aids to allow staff to continue working in white-out conditions that improves the safety of both those traveling on the roads and drivers, said Tina Greenfield, road weather information coordinator with the Iowa DOT’s maintenance bureau.

“The plowing situation is challenging even in normal conditions,” Greenfield said. “There’s a lot of snow that is cast up by the front plow as it’s plowing. … (Drivers) live in a constant snow cloud, just because of the nature of their job. And, then, when it gets really bad out — when the wind is howling and the snow is blowing — it’s hard to see where the road is.

“If they can’t see where they’re going, they can’t really be out there and plowing. When we pull off, that’s when the roads really start to clog up. Once the plows have to pull off, the drifts start building.”

For the past year, ISU researchers have been investigating potential navigation equipment, taking lessons and cues from similar lane-departure and obstacle-detection systems used by state transportation departments in Alaska and Minnesota.

In late September, ISU researchers and a group of 20 snowplow drivers from around the state gathered in Ames to look at options and provide feedback, including which navigation and obstacle alerts and user interface would be most useful.

And earlier this month, researchers traveled to the Iowa DOT’s Tama shop to install the first iteration of the equipment on a snowplow for testing.

Sensors mounted to the plow will feed information to equipment in the cab that processes it and displays the data on a tablet screen mounted on the dash.

Anuj Sharma, ISU professor in civil engineering and a research scientist at its Institute for Transportation, said the system being tested builds off those being used in autonomous vehicles now in development. Greenfield, though, stressed the equipment being tested will not automate any of the functions of the snowplow.

“The driver is still in charge of the plow truck,” she said.

Instead, the equipment will function similar to a blind-spot alert or lane-departure system one might have in their car.

It uses a combination of sensors, radar and LIDAR 3D scanning for collision avoidance and advanced GPS technology for navigation and lane management.

“Most modern cars today have lane-departure sensing that relies on cameras,” Sharma said. “But most of the time the road is covered with snow and so you can’t rely on cameras that can detect lane markings.”

Instead, the system relies on a database of high-definition mapping and high-accuracy GPS technology to determine where a plow is in terms of position in the lane and a display to show the truck’s position on the roadway and proximity to obstacles, such as a car, bridge piers and abutments and guardrails that may be covered by snow drifts.

Obstacle detection relies on the use of LIDAR, a remote sensing technology that uses the pulse from a laser to collect measurements to create 3D models and maps of objects and environments.

Alaska’s state department of transportation uses similar technology. Snow plows are outfitted with a "differential GPS" guidance system that uses information from ground stations, satellites and GPS receivers mounted atop the cab to pinpoint the vehicle’s location with an accuracy of 3 to 5 centimeters.

In the cab, drivers have a display that shows the truck's position relative to the lane markings on a moving map. If the truck travels over the lane marking, a solid red line appears warning the driver it has crossed out of the prescribed lane.

With the unpredictability of an Iowa winter, that would help keep trucks on the road in low-visibility conditions, the Iowa DOT’s Greenfield said.

That means potentially fewer motorists stranded in deep or blowing snow, better access for emergency vehicles, keeping roads from becoming completely impassable and quicker cleanup to get roads back to normal following a storm.

It also means improved safety and peace of mind for state snowplow drivers, said Brandon Lafrenz, highway maintenance supervisor of the Iowa DOT’s Grinnell, Malcom and Tama garages.

“I’ve been in storms where I have the driver’s door window down and I have by head hanging out of the window in blizzard conditions trying to find yellow paint to guide myself,” Lafrenz said. “It’s just dangerous. It will give that operator a sense of where they’re at on the road.”

Sharma and Greenfield said ISU researchers and the Iowa DOT plan to conduct closed-course testing this winter on the Tama snowplow to test the accuracy of GPS data and how the devices perform.

Greenfield does not anticipate having a prototype out on the road this winter. She said the research project is slated to be competed in October 2024.

Lafrenz said he hopes the system becomes cost-effective that the Iowa DOT can equip the technology on most or all of its nearly 1,000 snowplows statewide.

Comments: (319) 398-8499; tom.barton@thegazette.com