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Side impellers on a yoyo

  1. Sep 27, 2012 #1
    Well i know this sounds silly but I think that impellers on the sides of a yoyo would give greater stability than the current hollow ones.( Just to give you an idea of the type of yoyo's I'm talking about: http://shop.yoyoexpert.com/product/162/Juggernaut [Broken]). I haven't started a cad model as I don't really have time to waste on a fruitless effort considering how close midterms are.

    Basically the idea is that the impeller would suck air in from the side face of the yoyo and blow out from the side. This is just a hypothesis and I am just a first year student in mech.eng so sorry for the ignorance.
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Sep 27, 2012 #2


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    Please elabourate: What instability are you referring to? Your idea may be innovative and useful.

  4. Sep 27, 2012 #3
    You'll see how silly it is once you do gyroscopic motion in advanced dynamics.
  5. Sep 27, 2012 #4
    Yoyo's tend to move around with slight movements from the wrist, usually a swinging motion
  6. Sep 27, 2012 #5


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    sadben, unlike the poster #3, I am not so quick to dismiss your hypothesis as silly. You may have a new, unique, and innovative idea. I would hope that when you find the time that you experiment with your hypothesis. Any true searcher would at least try. Who knows, maybe there is something else the impeller(s) could do? And maybe not. At least record the idea in your notebook. Years from now you may discover some cool way to use it.

  7. Sep 28, 2012 #6


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    A yoyo gets its stability from gyroscopic stabilization through angular momentum; the faster it spins the more stable it is. In addition, the longer it stays spinning at a fast rate the better, so you want its air friction to be as low as possible to achieve this.

    Adding "impellers" to the sides of it would increase air friction, slowing the yoyo more quickly. This would be a bad thing in Yoyo design, and hence a bad idea unless you plan to utilize the net force from the "impellers" to achieve yoyo tricks not possible with conventional designs (say for example levitation or mid-air transversing, probably not possible).
    Last edited: Sep 28, 2012
  8. Sep 29, 2012 #7
    I'm thinking the the OP was talking about bringing in air axially and ejecting it radially, like a centrifugal blower or pump.

    OP, it certainly could be made but it wouldn't increase the stability of the yo-yo. If anything it would slow it down and make a cool whirring noise.

    Speed and mass are the only ways I know of to fight precession and drift.

    As far as Vadar's post, well....no comment.
  9. Oct 1, 2012 #8
    I wasn't calling the idea silly, was just giving him a hint as to what to look up to determine it himself. I was mainly pointing out what Mech_Engineer stated, but didn't want to spoil it.
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