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Engineering Project Help Please Creative Minds

  1. Oct 22, 2008 #1
    Engineering Project Help Please!!! Creative Minds!!

    OK, so I need some help guys, I have an engineering project that was recently assigned to me and basically the main goal is to construct a model transportation device (2’x2’x4’ maximum) that can go the farthest and hold the most water weight (a formula was made by the judges to balance out both of these to make it even). However the rules are that you may not use any form of electrical devices whatsoever, nor can you use any liquid flammable objects such as gasoline or any rocket fuels. Another rule that was actually placed in recently was that no animals are allowed to be involved (which I found quite funny).

    So basically of course I’ve thought of the old wind up and go technique, or even a way of propulsion through CO2 canisters, but can anybody please help with any creative ideas that I’ve simply passed by please??
     
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  3. Oct 22, 2008 #2

    Mech_Engineer

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    Re: Engineering Project Help Please!!! Creative Minds!!

    How about using potential energy stored in the water itself, either by transferring the water from a higher tank to a lower tank, or attaching a mechanism that allows the tank to drop down.
     
  4. Oct 22, 2008 #3

    Danger

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    Re: Engineering Project Help Please!!! Creative Minds!!

    Or you could combine the 2 techniques. Pressurize the tank with the CO2 and use it as a water rocket. :biggrin:

    Of course, your vehicle would no longer have the required weight at the finish line.
     
  5. Oct 22, 2008 #4
    Re: Engineering Project Help Please!!! Creative Minds!!

    yea, the potential energy using gravity could possibly work. But, with the other idea, i forgot to mention that you get penalized for any weight that is lost throughout the run, so i cannot dispose of any of the water or obviously have something get left behind on the track
     
  6. Oct 22, 2008 #5
    Re: Engineering Project Help Please!!! Creative Minds!!

    This project sounds like a lot of fun. I really like the idea of using potential energy in the water as a method of propulsion. This is probably a bit too complex, plus the distance gain may or may not give you a higher score (because some of the vessel must be left empty for the flow to work well).

    The vessel would be divided into two levels. There would be an opening in a portion of the division with a water-mill attached to the drive train.

    Sounds like an interesting idea, but I have the feeling the small distance gained by the energy harvested from the falling water would be negligible compared to the extra water that could be contained in your vessel.

    You're allowed to attach CO2 canisters for propullsion? Are you allowed to use any other methods of launch such as spring-loading it? And how about other methods of propulsion besides combustion, like baking soda + vinegar (I don't know a whole lot about chemistry, I've only had one year of it so far). Is there any stronger concoctions that don't require combustion but still expell energy? I'm guessing something like HCl + H2O out of the question?

    Does the entire vessel need to fit into a 2x2x4 space, or can you have a long pole stick out from the top of it, and just have the part containing water 2x2x4? I'm assuming it's the former, but if it's not, then you can have a long pole come from the center of your vessel. Inside the pole is a string wound around an axle (or attached the the drive train by other means) then going through the center of the pole. At the top of the pole, the string would be attached to a heavy steel weight that will be released and make the vessel go.

    Edit: But the wind up technique seems at first glance that it would be the most effective.

    Good luck! I can't wait until I start projects like this. :) Is this for college or high school?
     
  7. Oct 22, 2008 #6
    Re: Engineering Project Help Please!!! Creative Minds!!

    yea i agree with you about the potential energy, while it may work, it does seem like it could be a bit too complex and i may not get the best score with the technique.
    But yea you can use CO2 cannisters and spring loading (which was my original idea as a combination of both).
    And yea you can use other techniques such as baking soda and vinegar but the only problem is that im not quite sure which mixtures produce the greatest amount of energy, how to harness the energy from it, and overall how much it will actually do for moving a car of water.
    Also, no im not allowed to use anything outside of the 2x2x4, so no pole =/. And this is for my freshman year in college.
     
  8. Oct 23, 2008 #7

    Danger

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    Re: Engineering Project Help Please!!! Creative Minds!!

    That would pose a problem with the CO2 as well, then, since its density is higher than that of air. Maybe you could carry a helium bladder and bleed it off to counter-balance the CO2 loss... :uhh:
     
  9. Oct 23, 2008 #8
    Re: Engineering Project Help Please!!! Creative Minds!!

    Since your project will have a fixed volume, using the potential energy of the water is going to reduce the amount that it can carry. I would just keep it simple, compressed air (it doesn't have to be CO2) and a pneumatic motor should work pretty well.
     
  10. Oct 23, 2008 #9

    Danger

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    Re: Engineering Project Help Please!!! Creative Minds!!

    You don't have to work out a mixture for that stuff; it's self-regulating. They use each other up until only one is left. You would lose a lot of mass with that approach, though.
    How about a combination based upon my water rocket idea? You could do the CO2 pressurization of the water tank, but then force the water jet through a turbine or paddle wheel and collect it in a second tank as would have occurred in Mech's original plan. You wouldn't even lose the CO2, since it would be trapped in the top of the source tank.
     
  11. Oct 29, 2008 #10
    Re: Engineering Project Help Please!!! Creative Minds!!

    use a massive flywheel ...
     
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