UMaine Engineering Students Gear Up for International Snowmobile Challenge
Contact: Michael Peterson, Mechanical Engineering, 207-581-2129; Nick Houtman, Dept. of Public Affairs, 207-581-3777
ORONO– Want to know the future of snowmobiles? Just ask a member of the University of Maine’s Clean Snowmobile Challenge team. Thirteen students in the Dept. of Mechanical Engineering and three students in Mechanical Engineering Technology are installing sensors, writing software and designing and building their own diagnostic equipment in preparation for the March 14-19 international competition at Michigan Tech in Houghton, Michigan, sponsored by the Society of Automotive Engineers (SAE).
“After a third place finish last year, we think we have a design that can threaten the dominant position of University of Wisconsin-Madison,” says Michael L. Peterson, associate professor in the Dept. of Mechanical Engineering and the team’s co-advisor. “Wisconsin built a hybrid electric snowmobile, but for overall performance, we think that we have a competitive design.”
The students have divided into groups focusing on computer modeling, dynamometer design, fiberglass construction and an exhaust gas sensor system. Two additional groups are building custom equipment for testing the new snowmobile designs. Their goal is a machine that not only performs well but leaves the air fresher and uses less fuel than its predecessors.
The team’s focus is a 2003 Arctic Cat snowmobile equipped with a four-stroke engine. When students are done with it, the machine will have a whole new personality. In addition to Peterson, Chuck Maguire in mechanical engineering technology advises the team. Financial support has come from Applied Thermal Sciences in Sanford and the College of Engineering and Dept. of Industrial Cooperation at UMaine.
The work began last fall in Crosby Lab on the UMaine campus as students began by looking for opportunities to increase the machine’s efficiency. “There’s been so much improvement of snowmobile engines, we didn’t think we could get much more out of the basic engine design,” says team member Adam McNaughton of Newport. “We’ve been focusing more on ways to get the pollutants (in the exhaust) down.”
McNaughton and four other students are installing a sensor system that will analyze exhaust gases and send a signal to a microcontroller. Using instructions written by the students, the microcontroller will adjust the signals sent to the engine’s stock engine control unit to make better use of the catalytic converter that was adapted to the engine by last year’s UMaine team. This combination will keep exhaust gases as clean as possible.
“The catalytic converter reduced hydrocarbon emissions from about 130 parts per million to about 20,” said McNaughton. “With the new engine electronics, we think we have gotten that down to about 12. This compares to 1600 parts per million for the 2-stroke Ski-Doo we worked on three years ago, and that was with some significant tuning improvements!”
Other members of the sensor group are Aaron Phinney of Hermon, Steve Geller of Waterville, Mike Peabbles of Gray, Chris Richards of Buxton, Corey Hibbard of Bingham, Warren Peters of Gorham, Jon Souliere of Dayton, and Alex Daigle of Madawaska.
Since a machine needs to look good as well as run efficiently, another group has built a new fiberglass fairing, the lightweight cover that protects the engine and reduces wind resistance. The fairing is also key to keeping the machine quiet, another important factor in the competition. They began by making a form out of wood, Styrofoam and automotive body filler, sanding and shaving it to assume the shape of the finished product. Completing the new fairing required two additional steps: creating a fiberglass mold by layering glass fabric and liquid resin over the form; and repeating the process by making the fiberglass fairing itself inside the mold. The design is unique in that it uses sound deadening materials that are built right into the structure.
Members of the fairing team include Trevor Jenkins of Sebec, Kyle Spratt of Frenchboro, Steven Cook of Jay and Kate Charles of Bangor.
Making sure that the machine is running to their specifications requires hooking it to test equipment known as a dynamometer. The students could have spent $6,000 for a digital off-the-shelf model. Instead they decided to build one from scratch, using sensors and a laptop computer that displays sensor signals on screen.
“We had to learn the electronics from the beginning,” says Brian Parent of Van Buren. “None of us were experts in it. Now we can expand this system to monitor almost anything.” In addition to Parent, students working on the dynamometer include Craig Michaud of Frenchville and Ryan Crawford of Freeport.
In industry, new products are designed on a computer before machinists grind metal on a shop floor. Phinney and Geller filled that role for the UMaine team by modifying a computer model that predicts the consequences of changing basic features of the engine, transmission, clutch and other mechanical components. “For example, being able to change something like the top engine speed helps us see how that affects exhaust or fuel economy,” says Phinney. The students have also improved model documentation, a written report that describes the modeling procedure, lists the software code and describes applications used in the design process.
To competition judges, how well the team explains and demonstrates its work is as important as how well the snowmobile performs. “We think we can make a big improvement in that area over what we did last year,” adds Phinney.
The competition will be held at the Keweenaw Research Center at Michigan Tech, known for its vehicle test grounds and as the Midwest’s finest winter driving track. Other participating universities include: Clarkson University in New York, Kettering University in Flint, McGill University in Montreal, Michigan Tech, Minnesota State University at Mankato, Montana Tech, the State University of New York at Buffalo, the University of Alberta, the University of Idaho, the University of Wisconsin-Madison and the University of Wisconsin-Platteville.
General information about the competition is available at http://students.sae.org/competitions/snow/.