New research would make clearing roads in Iowa safer during a snowstorm

New research and technology could help guide Iowa snowplow drivers in white-out conditions and warn them of obstacles, improve driver safety, and keep 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 will allow its employees to “see” better in inclement weather. It involves equipping snowplows with sensors and driving aids so employees can continue working even under white-out conditions, improving the safety of both road users and drivers, said Tina Greenfield, road weather information coordinator at the Iowa DOT’s maintenance office.

“The plowing situation is challenging even under normal conditions,” said Greenfield. “There is a lot of snow thrown up by the front plow when plowing. … (drivers) live in a constant cloud of snow just because of the nature of their work. And then when it gets really bad – when the wind howls and the snow blows – it’s hard to see where the road is.

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“If they can’t see where they’re going, they can’t really be out there plowing. When we leave the roads really start to congest. As soon as the plows have to pull away, the drifts start building.”

Over the past year, ISU researchers have studied potential navigation devices, drawing lessons and clues from similar lane-keeping and obstacle-detection systems used by state transportation agencies in Alaska and Minnesota.

In late September, ISU researchers and a group of 20 snowplough operators from across the state gathered in Ames to review options and provide feedback, including which navigation and obstacle alerts and user interfaces 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 on the plow relay information to devices in the cab, which process it and display the data on a tablet screen mounted on the dashboard.

Anuj Sharma, ISU professor of civil engineering and research scientist at the Institute of Transportation, said the tested system builds on those used in autonomous vehicles currently under development. However, Greenfield stressed that the tested equipment will not automate any of the snowplough’s functions.

“The driver is still responsible for the plow wagon,” she said.

Instead, the equipment works much like a blind spot warning or lane departure system you might have in your 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 camera-based lane departure detection,” Sharma said. “But most of the time the road is snow-covered, so you can’t rely on cameras to see lane markings.”

Instead, the system relies on a database of high-resolution mapping and high-precision GPS technology to determine where a plow is in relation to its position on the lane, and on a display to show the truck’s position on the lane and the Show proximity to obstacles such as a car, bridge abutments and abutments, and crash barriers that may be covered by snowdrifts.

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

The Alaska Department of Transportation uses similar technology. Snow plows are equipped with a “differential GPS” guidance system that uses information from ground stations, satellites and cab-mounted GPS receivers to determine 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 lane markings on a moving map. If the truck crosses the lane marking, a solid red line appears, warning the driver that he has left the prescribed lane.

Given the unpredictability of an Iowa winter, this would help keep trucks on the road in poor visibility, Greenfield of the Iowa DOT said.

That means potentially fewer motorists stranded in deep or blowing snow, better access for emergency vehicles, preventing roads from becoming completely impassable, and faster cleaning to restore roads to normal after a storm.

It also means increased safety and peace of mind for state snowplow operators, said Brandon Lafrenz, road maintenance supervisor for the Iowa DOT’s Grinnell, Malcom and Tama workshops.

“I’ve been in storms where I’ve rolled down the driver’s door window and hung my head out the window during blizzards, trying to find yellow paint to orient myself,” Lafrenz said. “It’s just dangerous. It’ll give that operator a sense of where he is on the road.”

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

Greenfield doesn’t expect to get a prototype on the road this winter. She said the research project is scheduled to be completed in October 2024.

Lafrenz said he hopes the system will be cost-effective for Iowa’s DOT to fit the technology on most or all of its nearly 1,000 snowplows statewide.