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MIT Competition: Battle of the Crazy Machines

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Leaders and Liars

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SHOW 301: MIT Competition: Battle of the Crazy Machines

Back by popular demand, it's the MIT student engineering competition -- the ultimate test of inventiveness and ingenuity. Contestants, actually students in a design course at the Massachusetts Institute of Technology, are given identical kits of assorted machine parts and motors. The assignment? To turn this box of "junk" into a vehicle that delivers a load of ping-pong balls into a trough... all while fending off an opponent's vehicle.

Curriculum Links
Activity: Simply Marvelous Machines
Math Connection
Notes & Discussion
Report From the Field: Thomas Massie, Electrical Engineering Major at MIT




energy and work


Each year, engineering students in a design course at the Massachusetts Institute of Technology (MIT) are given identical kits of assorted materials, which may include such unrelated items as a cardboard tube, constant force spring, an O-ring, a giant paper clip and half of a plastic robot head. The challenge is to design and build a device that will accomplish a specific task better than any of their classmates'. As you see on SCIENTIFIC AMERICAN FRONTIERS, students this year build machines to deposit ping-pong balls in a trough while fending off an opponent. Now it's your turn...


Machines can be very complex or very simple. You have probably used all of the six machines listed below at one time or another, maybe without realizing it. Simple machines form the basis of more complex constructions. For example, the complex machine we call a "car" is really composed of many different groupings of these six simple machines:

Lever, Inclined Plane, Pulley, Screw, Wheel and Axle, Wedge

Write down examples of each simple machine.


In this contest, you will use simple machines to build a device that can lift a steel or iron washer from a table top to a height of exactly 10 cm, then drop it from that height into a paper cup placed next to the washer.

  • Any combination of these six simple machines (the more, the better): lever; inclined plane; pulley; screw; wheel and axle; wedge
  • string or monofilament
  • iron washer
  • paper cup
  • magnet(s)
  • empty plastic soda bottles
  • mousetraps
  • drinking straws
  • coat hangers
  • steel spheres
  • marbles
  • water
  • etc.

  1. No electrical or battery-powered devices may be used. However, mechanical devices may be used.

  2. Any combination of simple machines may be used.

  3. No two simple machines may touch in any way (and inclined planes can't connect them!).

  4. Some object or objects (marbles, for example) must be moved through your device.

  5. The washer and paper cup must be placed next to each other on the table top, separated by no more than 10 centimeters.

  6. Once the motion starts, you may not touch anything on your device. The washer must be lifted from the table top and dropped into the cup without human assistance.

  7. Your device should have a theme.

  • Simple machines used: 2 points each

  • Everyday materials used to build simple machines from scratch: 10 points each

  • Object climbs up inclined plane: 1 point each cm

  • Object transported by wheel and axle or pulley. 1 point each cm x mass of object (g)

  • Object transported across a gap on a moving part: 1 point each cm

  • Object propelled across a gap: mass of object (g) x gap width x 2 points

  • Washer lifted to exact height of 10 cm: 10 points

  • Theme is evident (props, pictures, scenery, etc.): 2 points

  • Theme music played during operation: 2 points

  • Project works from beginning to end without human assistance: multiply total by 10

  • In this competition, students build a device using simple machines and ordinary household materials. The first part of the activity discusses simple machines, and is good preparation for the hands-on activity that follows. Examples include: lever/bottle opener; inclined plane/ramp; wedge/chisel; pulley/pulley attached to fan belt in car; screw/ corkscrew; wheel and axle/bicycle wheel. A good resource is The Way Things Work by David Maculae (Houghton Mifflin, 1988).

  • You may wish to form teams of three or four students for the hands-on activity. Heterogeneous groups work best.

  • A scoring system is suggested. You or the students may wish to add criteria, increase or decrease points, increase or decrease difficulty or delete items. (You may wish to eliminate the scoring process altogether.) It is important that students feel comfortable with all aspects of the challenge, including the possibility that their creation might not work.

  • You may designate a time limit on the competition, depending on the group. It works well as a week-long project or one that stretches out over a month.

  • Emphasize that NO electrical or battery operated devices may be used.

  • In case of a tie, the team with the quickest "run" wins. Conduct the runs one at a time. Prizes offer an incentive but are not absolutely necessary. Local businesses may wish to contribute prizes.

  • Encourage students to take risks. Sometimes, with such an open-ended activity, the fewer instructions given, the better the inventive process.

  • Form groups of four students each. Tell students they must transport a 1-ton block of gold 1 kilometer up a hill. Have groups describe how they would use a combination of simple machines to accomplish this task. Tell students they may not use a motor in their solution to the problem. Have groups share their ideas with the class and discuss the best possible solution.

  • Competitions promote the concept that teamwork, careful planning, readjusting after a failure and the identification and elimination of bad devices leads to success, no matter how small. Not every MIT student who built a vehicle can win, but every MIT student who participated took away vital lessons.

  • You may want to show part of the tape, talk about what you've seen, then ask students what strategy they think will win. Other possible discussion topics include: What part does brain-storming play in the invention process? What advantages might a team have over an individual? How is "success" defined in science? Failure? How do we learn from failure? Find examples of other scientists and inventors who had to go through numerous trials before their idea "worked."


As winner of the MIT 2.70 competition, Thomas Massie fulfilled a dream he's had since adolescence. He recalls, "I can remember sitting in my living room watching 2.70 on TV, before I even knew that MIT was in Massachusetts. I thought the contest was incredible -- in fact, I taped it on my VCR and watched it again. It greatly inspired me and was a big factor in my decision to attend MIT and pursue engineering in general.

"I was born in West Virginia and grew up in Vanceburg, Kentucky, a town of 2,100 people. I always used to take apart clocks, toys, cash registers...anything I could get my hands on. Because I lived in the middle of nowhere, I had to be resourceful when I built things like robot arms for science fairs in high school. Mom's kitchen appliances, Dad's tools and flashlights, and my brother's and sister's toys would mysteriously disappear whenever I needed more parts. Hey, it was the only way I could get things then!

"The kits they give us in 2.70 contain many items identical to those I found in toys, clocks and appliances. Much of it would fall under the classification 'junk'."

To Massie, junk is just another word for parts, and parts can be used to build things like the self-watering flowerpot he constructed in high school. In this device, and dozens of others like it, Massie ran into obstacles. While the pump from a water reservoir worked fine, the on/off electrical circuit didn't, and drained the battery in about a week instead of the two years he calculated. Design flaws like these motivated Massie to learn more about the mathematical formulas and scientific principles he needed to make his ideas work.

Today, as part of his research at MIT, Massie is working in the school's Artificial Intelligence Lab, where he's designing high-speed force-sensitive robots, which have a number of potential practical applications, such as underwater exploration, outer space probes and nuclear waste clean-up.

Massie concludes, "It doesn't matter if you live in the middle of Nowhere, USA -- you can always find junk. So, anybody, any age, anywhere can build wonderful things...with a little imagination."


Scientific American Frontiers
Fall 1990 to Spring 2000
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