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Mechanical engineering students show their stuff.
by Elizabeth Quan
Imagine that you're a contestant on the hottest TV game show or - let's get real here - you're playing a trivia game at home with your family during vacation. It's your turn, and the clue is "robot." Think fast - what images come to mind? Chances are you'll think of stalwart little R2D2, the menacing automaton from your latest science fiction read, or a recent tabloid cover story you skimmed while waiting in the supermarket checkout line.
Or just maybe you'll raise your arms in victory and shout, "ME 2011!"
If that's the case, then you're probably one of the 200 or so lower division students who spent the last six weeks of spring semester immersed in the capstone project for Introduction to Engineering - the design and production of a computer-operated machine. The project culminates in the annual robotics fair, during which students show off their robots to a panel of judges, their fellow students, and the general public. The site of this year's fair, held on May 3, was spacious Memorial Hall in the University's new McNamara Alumni Center/University of Minnesota Gateway.
The project entails the design and construction of a computer-operated machine according to strict rules and regulations on size, action time, safety, power source, parts, and human intervention. Several checkpoints are built into the process to provide students with guidance and problem-solving assistance. Students meet in support groups to discuss ways to improve their products and overcome the inevitable snags that arise.
Students must submit several concept drawings and keep a detailed account of activities, ideas, parts searches, and information in a sketchbook. The actual construction of the robots occurs outside of class.
Robot support group members express varied opinions on the process, which demands frequent redesign and repair of their robots. Some students admit that they found the experience a bit daunting, saying, "There's a lot to learn." Others enjoyed it immensely, even the difficult moments, saying, "It's fun!"
The course instructor, mechanical engineering professor William Durfee, stresses the value of incorporating electronics into mechanical engineering. He says the robot project provides both hands-on experience and an accomplished product to show employers. In addition to the robot itself, students must organize a presentable portfolio that contains a resumé, hand sketches of previous assignments, Excel data and plot, and samples from the sketchbook.
The sophomore-level class encourages students to prepare for job searches. Durfee frequently reminds the students, "Your robot shows what you can do."
The course accommodates a broad range of demonstrated applications and skills, so it's possible that the course may eventually be open to freshmen. Because the course work entails many sketches and drawings, the class might also be offered to art majors in the College of Liberal Arts.
Durfee's collection of the students' concept drawings reveals obvious differences from their first ideas and the evolving designs. And when construction begins, students find themselves caught smack in the middle of the contest between their design concepts and physical laws. They learn very quickly where to place their bets.
As the project deadline approached, students experience "99% perspiration." Although some students complete their projects before the robotics fair, many others are still frantically making repairs and modifications. Before and even during the show, students cope with such emergencies as broken pumps, welding fractures, or tracks that needed cleaning.
With the fair date in sight, students soon discover that time management is a critical skill. The project deadline coincides with end-of-the semester "crunch time" in all their classes. There are stressful and frustrating moments as students cope with the experimental process, which is full of surprises.
One group member who struggled to get all the parts working in his "lock and dam" robot admits that he might not have a have a dam after all. Eventually the student comes up with a successful, modified version of the lock and dam. Another student found that individual parts for a robbery scene worked, but he speculates that the parts might not work together.
Stephan Hertel summarizes his technical difficulties: "The altitude goes up. Weight of the cable goes up. We lose buoyancy."
Yet another student flips through her concept drawings and sketches, which reveal overwhelming effort. She looks at the computer code that controls her robot and asks her group, "How should I get this to work?"
Regulations specify that the robot's actions are limited to 45 seconds in duration and must be repeated shortly after reset. The projects combat the stereotype that robots are a manifestation of humans. The human imagination visualizes robots that can perform miraculous feats, but in reality they are simply computer-controlled machines designed to perform a task.
On the day of the fair, students rush to the gateway center to set up their projects and complete last-minute repairs. Judges from 3M, the University, and other organizations inspect and evaluate several of the more than 200 robots. Their evaluations form the basis of course grades. Students are kept busy activating and explaining the functions of their robots.
Liz Llewellynıs robot "Darth Maul Versus the Bantha" uses a timer and a computer. A marble rolls onto a roller coaster and into a box that tips a teeter-totter, triggering a mousetrap. The mousetrap pulls Bantha out of a box, and then Bantha knocks over Darth Maul, a Lego man.
She admits that having to rebuild her robot was frustrating but acknowledges she had fun and learned from the project.
"It is a relief. My project works every time," says Llewellyn. "I learned many things.... [For example,] it always takes longer than you think, [including making] directions for people to build. Someone has to be able to rebuild your creation. It's a real-life application."
Hertel's eye-catching display of balloons flies around in a pre-programmed flight path, with helium providing natural buoyancy. Fans exert force or thrust to raise or lower the balloons. The control unit is constructed almost entirely from scratch.
He says, "This wasn't too bad. I took one step at a time." He found the class to be worthwhile, especially the CAD drawings. There "was a lot of busy work, though."
Alan Fruland's robot jigs three times and reels up a fish. A bidirectional motor controls the action. He says, "It's all in the timing."
For many students, their greatest fear was that a part would break. Joe Smith, whose project reels a lion into a cage that lifts, agrees that parts break easily. Fortunately, many materials used were items students found in their homes.
The soon-to-be mechanical engineers realize that they're taking the first steps toward careers in which they'll create machines that could make life easier for everyone. According to many class members, the sense of accomplishment stemming from the inspiration certainly was worth the perspiration.
Fruland says, "This class is definitely worthwhile. It might even end up to be my favorite class in college."
