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| Home : Volume 32 : Winter 2006 | |
| New student team builds vehicles powered by legs — not fossil fuels | |
Human-powered Vehicle Team member Nicole Zobel riding "Badger Lightning" in the 2005 national competition |
It was over with a snap. The UW-Madison Human Powered Vehicle Team had spent months building “Badger Lightning” and transported the vehicle all the way to Tuscaloosa, Alabama. Then, just minutes into the second day of national competition, the three-wheeler's frame suddenly cracked.
“I was completely bummed,” says Paul Harder, one of the squad's leaders. “I thought we were heading home.”
The team's first race, a sprint, had gone well. The group also earned rave reviews for its aluminum frame, one of just a handful in the contest. But only moments into a slalom race studded with obstacles, the vehicle took a bump too hard and the frame gave way.
The 2005-2006 Human-Powered Vehicle team with faculty advisors Frank Pfefferkorn and Heidi Ploeg (far left) |
All seemed lost until a kind gesture by the supervisor of the University of Alabama's student machine shop put the team back on its wheels. After he helped the group transport its damaged vehicle to the shop, team co-founder and vice-president Dusty Brunner used a borrowed welder to mend the frame, eyeballing the alignment because of a lack of tools.
The next day, Badger Lightning's patched-up frame held, and the vehicle went on to finish a 36-mile endurance ride. And with that, the squad completed its first Human-Powered Vehicle Challenge, a collegiate design competition sponsored by the American Society of Mechanical Engineers (ASME). Not a bad showing for a team that had formed just eight months before.
“They did well,” says bicycle racer and Mechanical Engineering Assistant Professor Heidi Ploeg, who advises the team with ME Assistant Professor Frank Pfefferkorn. “In just their first year, they built something and they brought it down to the competition. And they got funding to do it. I was pretty impressed.”
The challenge, which encourages college students to design nonmotorized vehicles for safety, performance and practicality, draws teams from dozens of schools around the country. Students can fashion practical vehicles for use in everyday activities like commuting and grocery shopping or they can focus on speed.
When Brunner and team president Jessi Sanfilippo founded the UW squad in the summer of 2004, the team went practical with a vehicle that could carry loads and take on obstacles. But practical doesn't equal plodding or clumsy. Badger Lightning clocked 23 mph in competition. And it includes two elegant and ambitious components: a molded polycarbonate windscreen, or fairing, and a difficult-to-weld aluminum frame.
It's the chance to do some high-performance engineering that attracts students like Brunner. “The bike needs to be very lightweight and quick,” he says. “We're trying to push engineering to its limits.”
Although the team has grown now to 21 members, it's still small enough that “everyone has a hand in something,” says Brunner. The group is divided into seven committees, each of which handles one aspect of vehicle design, such as the frame, seat or fairing. More experienced members encourage and help their younger teammates, many of whom join with little or no hands-on skills. For example, this year Brunner will teach others the tricky task of welding aluminum.
With a year of experience under their belts, the students are also planning some serious design upgrades. To enhance vehicle performance and handling, they will switch to rear-wheel steering and front-wheel drive. They will also reduce the seat's size and the vehicle's length, changes that should cut weight and improve turning radius.
Most ambitious is a plan led by Brunner to add an energy storage system to the front wheels for capturing mechanical energy normally lost as heat during braking. The rider could then tap the stored energy to help propel the vehicle up hills.
Competent as they are, the students can't tackle these challenges alone. Area companies Advanced Design Concepts, Sub-Zero and TREK Bicycle gave them expert assistance in design and manufacturing last year. This year, TREK will help with one more critical fabrication step: heat-treating the aluminum frame. Welding aluminum can weaken it, explains Brunner, while heat treatment restores the metal's strength and protects against fracture.
“So when our frame doesn't break this year,” jokes Harder, “we should definitely get in a lot more riding time in competition.”
But more important than the contest's outcome is the process of preparing for it — and what the students gain as a result.
“Projects like the human-powered vehicle are a really effective and fun way to experience what it's like to actually work as an engineer,” says Harder. “And employers seek out job candidates who have proven teamwork skills on projects like this. In a job market where everyone has taken classes, it's a great way to set yourself apart.”
Content by perspective@engr.wisc.edu
Date last modified: 03-Feb-2006
Date created: 03-Feb-2006
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