Balloon Powered Car

Argh, more Project Based Learning.

Spec:

• "car": I guess that means 3+ wheels, which stay in contact with the ground. I guess that have to actually roll, and not be de-facto sled-blades...

• to be powered by 1 balloon: so you need some way to hold it in place, and direct nozzle in proper direction

  • hrm, "production" balloon to be issued in class, so can't pre-attach anything to it, like a nozzle.

• use only waste materials: no toy parts, no purchased parts

• outcome metric: linear distance travelled

There's already plenty of documentation online.

Out-of-box idea (from others, not me): don't inflate the balloon, use it like a rubber band, twist it then like it spin propeller like a rubber-band-plane. But you'd need a good-quality propeller, not easy to make. (Or you could have some sort of gear-drive instead of propeller, but again not realistic to hand-make.)

Ideas

• nozzle at end of balloon

  • pen body as nozzle, hold in place by wrapping rubber band around assembly

  • fix nozzle pointing up a bit, so that force is downward to keep it on surface

    • if back wheels are bigger than front wheels, then base is higher at back, so nozzle can be parallel to base

• base:

  • corrugated cardboard: put axles right in between waffles

  • cut base from some container to have bit of sides (do sides have a function?)

• axles

  • straws

  • toothpicks, bamboo skewers

  • straw as axle holder, with skewers running through

• wheels

  • plastic soda-bottle lids (hrm, we don't use those)

  • milk-bottle lids

  • baby bottle nipple/rim: might be stretching rules, but we are due to take them away from Number Three...

  • cut disks of plastic from a take-out tupperware