Iteration and efficiency

Arch-BridgeEfficiency is important in engineering, not only in materials but also time, money and energy. It is important for a young engineer to learn the value of an efficient product. Anyone can build a bridge with as many pieces they desire, but can you do it with fewer and fewer?

Challenge: Build a bridge that can hold a specified amount of weight. If it successfully holds the weight, rebuild the bridge using 20% fewer pieces. Every time you are successful, continue to remove pieces. Whoever can hold the weight using the fewest pieces is the winner of the challenge.

Students will be surprised at how many times they can iterate on their bridge and how much more efficient they can be in the use of the bricks.

We tested out this challenge ourselves and built a 1 ft bridge to hold a large water bottle. Our first bridge was comprised of 51 pieces, which we cut down to 40 and then further cut down to 32 pieces.

This challenge can be changed to keep the same number of pieces but change the overall length of the bridge by 10% each iteration.

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The Tufts Center for Engineering Education and Outreach (CEEO) in Boston, Massachusetts, is dedicated to improving engineering education in the classroom, from Kindergarten to college. The Center houses faculty, staff, and graduate students from engineering disciplines and the education department.

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