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Ways of powering vehicle that is not electricty or combustion.

  1. Oct 24, 2008 #1
    As part of my introductory engineering class this year, I have to work with a group to build a small vehicle (no bigger that 2ftx2ftx3ft) that can carry some water up to 250 ft. However, we cannot use any electricity, anything flammable or solid rockets. So right now I'm at a loss as to how to give this thing enough power to carry 1/2 lb. of water 100 ft. (my goal right now).

    Compressed air, CO2, and chemical reactions are fine, but I haven't found any good resources on how to make use of any of those for a car type thing that needs to carry something.

    Any ideas or resources I could look into?
  2. jcsd
  3. Oct 24, 2008 #2
  4. Oct 24, 2008 #3
    windup a spring?
  5. Oct 24, 2008 #4


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    Compressed air can be vented into cylinders like an internal combustion engine. You could start by looking at how these guys do it...
  6. Oct 26, 2008 #5


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    Mahhosive elastic band?
  7. Oct 26, 2008 #6


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    gerbils running in a wheel!

    Or, on a more reasonable, if "old-fashioned" note, horses, mules or oxen pulling the vehicle.
  8. Nov 10, 2008 #7
    You should try to find someone that paint ball's. Paintball air tanks can be pressurized to 4500 psi safely and hold easily 70cu. Take two of these puppies and hook up a cheap home depot regulator and you have enough air to power a pneumatic tool like a sander or grinder. You could even use the exhaust of the first unit to power a smaller one. Add some pulleys and belts to the mix and you'll be all set.
  9. Nov 10, 2008 #8


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    Forget the pneumatic tools. Just turn that paint ball cylinder into a jet.
  10. Nov 10, 2008 #9

    When I was an elementary student, we used 'Nitrous Oxide gas pellets' to launch homemade model rockets, suspended on a string, horizontally across the school lawn. And when I was a Boy Scout, we used them to launch toy model race cars down a curved ramp.

    A 'cracker' is used to punch a hole in the nozzle.

    Good memories, and alot of fun!. . . I wonder what motivated me into physics anyway?

    Attached Files:

    Last edited: Nov 10, 2008
  11. Nov 11, 2008 #10
    What are the exact words used? Diesel oil isn't flammable under normal conditions... Nor is vegetable oil, and though many Diesel engines run very well on vegetable oil.

    You could even end up to concentrated H2O2. Not exactly flammable, but high energy contents, and pretty much dangerous (huge boom with no good reason). Was used as a monopropellant for rockets, still used for torpedoes.

    --------- OK, without cheating then:

    For simplicity, I would store energy in rubber. Natural rubber stores more energy per kg and per dm3 than steel springs do, this energy is easily converted in a movement, and force/displacements adapt more easily to a vehicle.

    Beware most synthetic rubbers (especially polyurethane) are slow and don't give all the energy back - they creep a lot. And beware no rubber is reproducible nor predictible.

    As a child I built dragsters with Lego and rubber bands. Fun. Damned fast. Now Lego sells some, of course not as good as mines. I just pulled the rubber by winding it around the axle, but twisting it as in a toy plane would work for a longer distance.
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