When University of Michigan football coach Fritz Crisler pioneered the winged helmet design worn famously by the Wolverines since the 1930s, it’s unlikely he knew his influence would reach as far as bathymetric surveys of remote lakes in Alaska.
In 2006, a collaboration between the University of Michigan and the Michigan Tech Research Institute brought Guy Meadows, Robert Shuchman and Liza Jenkins to the shores of some of the thousands of lakes that dot the Alaska North Slope. The lakes there are the source of water for ice roads that facilitate oil development in the region.
Regulations protect the lakes’ water quantity and quality. But with so many lakes and so little data, the rules can be difficult to follow and enforce. The lakes are accessible only by helicopter. The standard survey method of flying some scientists, equipment and an inflatable boat to a lake was slow going and expensive.
“The trouble is there are 156,000 lakes up on the North Slope,” said Shuchman, co-director of the Michigan Tech Research Institute. “Taking a Zodiac up there was one lake a day.”
“Only in the ice-free summer,” added Jenkins, a research scientist at the institute. “And the summer is only two months long.”
The U.S. Bureau of Land Management began working with the institute and the University of Michigan to speed up lake assessments and get a better handle on the volume of water in the lakes. Part of the solution was a highly portable remote controlled, electric boat equipped with a depth sounder and GPS. They called the craft Bathy Boat, short for the bathymetric data the boat collects on the contours of underwater surfaces.
Bathy Boat began as a joint project between the University of Michigan and Michigan Technological University. It has since transferred fully over to the latter’s new Great Lakes Research Center, where Guy Meadows is the director, and the Michigan Tech Research Institute.
Despite the transfer, the 25-pound, 3-foot boat is still topped with a replica of the winged helmet worn by the Michigan Wolverines football team. Just like the design helped coach Crisler’s quarterbacks keep track of their receivers and which way they were facing, it helped Bathy Boat’s pilots keep track of the craft at very long distances during a technology demonstration on the North Slope lakes.
“It turns out that the design actually helped us when we were way out at the fringe of the radio control of Bathy Boat,” Shuchman said. “Liza and I would look with the binoculars, and having that silly helmet would help us. ‘Oh, the boat’s going that way.'”
With its depth sensor collecting a measurement every second, the boat could collect data for a lake’s depth profile in the time it took for pilot to snake the boat back and forth across enough times to ensure sufficient coverage. Combined with satellite monitoring technology developed at the research institute, they turned what was once an all day affair into a relatively quick job that let the survey crew hit several lakes in a day.
Since returning from Alaska, Bathy Boat has proven useful anywhere that depth data is important but hard to come by. The Michigan Department of Environmental Quality recruited the tool to map shallow nearshore areas along Great Lakes beaches. That work is part of an effort to forecast rip currents and prevent drowning deaths this summer. A deployment along the Sleeping Bear Dunes National Lakeshore will help the National Parks Service track sand transport in shallow, boulder-strewn areas. As the Great Lakes hover around record lows, coastal marina operators are increasingly interested in depth data around their docks.
“It’s a very small portable device that can easily maneuver between pilings where larger survey vessels aren’t able to get,” Jenkins said.
Under the helmet, Bathy Boat carries off-the-shelf sensors for depth, temperature and conductivity. A GPS receiver and compass help with navigation and mapping the data. A Linux computer around the size of a cigarette pack conditions the data and facilitates its storage in flash memory. The motor and servos are high-end hobbyist models.
“I’ll use a technical term,” Shuchman said. “It’s cobbled together.”