wiggle drive propulsion application

Discussion in 'Propulsion' started by SudorracMechEng, May 7, 2012.

  1. swashdrive
    Joined: May 2012
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    Location: SEQ, Aus.

    swashdrive Junior Member

    G'day Mr Kjell

    The Swashdrive™, not "swash-drive"
    Works the same in reverse, but because i'm using a 3phase DC motor is not and easy as flicking a switch, also the fin foil shape is for forward motion !
    But yeah it goes backward !

    I see ur 2 pics as both swashplates, you see this motion or force of nature was discovered in 1910 by a man named Boris Yuriev and named a Swashplate, and so to call it anything other than a swashplate is completely false !

    wether you have a thrust bearing or roller bearing and whether you rotate the centre or rotate the rim of the bearing in a driven state or driver state that transverses rotation to reciprocation in this manner you are using a "Swashplate" not a wiggle something !
    regards
    craig
     
    Last edited: May 27, 2012
  2. Frosty

    Frosty Previous Member

    Mirage drive patented.

    http://www.hobiecat.com/kayaking/

    A surface piercing propeller is similar only it rotates instead of backwards and forward.

    Anything that revesses itself ie backwards and forwards wastes energy in doing so.
     
  3. swashdrive
    Joined: May 2012
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    swashdrive Junior Member

    Heah Frosty

    That is so wrong LoL
    As long as you keep rotating propellors you will continue to waste energy, like about 70% waste. This fin type propulsion is a lot better than that !

    Also this thread is not about a mirage drive at all, the only thing similar is they both have fins !
    http://www.youtube.com/watch?v=DtD09MTUsnE
     
  4. Frosty

    Frosty Previous Member

    A surface prop has blades only in the water for half its revolution. Its a continuous rotation. A rotating skulling device.

    A reciprocating engine at high RPM absorbs most power in itself by pushing and pulling pistons up and down to such a point a con rod can break.

    Your fins go back and forward ,--energy is absorbed changing the direction.
     
  5. swashdrive
    Joined: May 2012
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    swashdrive Junior Member

    what ever :rolleyes:
     
  6. Frosty

    Frosty Previous Member

    Oh -- it was (like 70% waste ) 5 minutes ago.
     
  7. Boston

    Boston Previous Member

    looks pretty cool to me. On a typical shaft drive prop you get inefficiencies at the hub and at the tips, here you've got fewer tips and no hub. Also the faster motion of a prop means higher frictional losses, not so in the slower moving fin. Someone should build a full scale test bed and see how well it does. If you could combine drive fins with stabilizer fins you might really have something ;-)

    get after it guys, I might want if for my retirement build.
     
  8. Frosty

    Frosty Previous Member

    Its old stuff Boston --my mate has one , had it for years Hobby cat with Mirage drive.

    Its very tiring because it goes up and down so you have to lift your leg off to push the other down.

    Its just a toy its just a pedalo, it needs a duck head on it.
     
  9. Boston

    Boston Previous Member

    nah, I'm thinking of a larger one for the cat. Who knows just an idea but it might be fun exploring it.

    I just like the idea of an all fin drive. Seems a lot cheaper to replace a bent fin than a bent prop. That and you could rotate them from the vertical to the horizontal in shallow water. Bring them up under the bridge deck and just go slow when in port. Could be really cool if it also was able to compensate a bit for pitch and roll.
     
  10. swashdrive
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    swashdrive Junior Member

    its definetly not a mirage drive, they use bell cranks and chains, we are using swashplates to manipulate the fins....totally different.
    I like the duck idea, could make for a silent running decoy....Hmm

    Its definetly a very different beast to drive than ur typical model prop boat or Jetboat, throttling up is tricky.
     
  11. SudorracMechEng
    Joined: Mar 2012
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    Location: australia

    SudorracMechEng Junior Member

    Hi everyone. First of all - This method DEFINITELY can give higher efficiency's than conventional propellers. I have done a lot of research into biomimetic propulsion and efficiency's as high as 87% have been validated.

    The major (observable) difference between the "KJELL wiggle" and the SwashdriveTM that i am trying to fundamentally understand, is KJELL only allows the pitch and the rolling motion to be of the same magnitude. Whereas, SwashdriveTM allows for different magnitudes between pitching and rolling motions.

    How is this achieved?

    Also, according to literature - most mechanisms were set up using a sinusoidal pitch and sinusoidal rolling motion with a phase lag of 90 degrees between. However as a result, the angle of attack was not found to be optimal for efficiency production. Modifying the pitching motion to follow a multifrequency motion allowed for the angle of attack to follow a cosine path. This was observed to very high efficiency's.

    However, since the mechanisms we are using have a single motor, and limiting parts - keeping the rolling and pitching to sinusoidal motion, with a phase lag of 90 degrees is optimal for testing. Doing this, it is vital that rolling and pitching magnitudes can be varied seperately

    This is why i want to work out how SwashDriveTM managed to get this ability to have a magnitude of rolling different to that of pitching?
     
  12. kjell
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    kjell Senior Member

    To reverse the rotation on a 3 fase motor,You only need aTwo Pole Double Throw Switch.
     

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  13. kjell
    Joined: Aug 2005
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    kjell Senior Member

    Are you the inventors of the Swashdrive Tattoo Machines ?
     
  14. swashdrive
    Joined: May 2012
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    swashdrive Junior Member

    Gday


    Stroke / Pitch is easy, once you understand the swash motion, i will try to explain as simple as possibly.
    Take a Large coin or bearing, stand it on its edge and spin, as it slows it will fall into a decaying motion. that is in essence is the motion we are using.
    Heres the example;
    If the coin (swashplate) has a 30 degree pitching angle it has a total stroke of 60 degrees. Given that 30 degree is achieved in 180 degrees of swashplate shaft rotation and the following 30 deg in the other 180 deg of shaft rotation. The fin follows the prefect cosine motion, you cannot get it any better because that is how nature does it, it is a special type of decay mechanism, not a bell-crank & chain.

    hope this is some help
    regards
    Craig
     
    Last edited: May 30, 2012

  15. SudorracMechEng
    Joined: Mar 2012
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    SudorracMechEng Junior Member

    Yes, i definitely understand the principles of a swash plate - my confusion was taking the neutral axis as zero, instead of the point to point rotation.
    So how are you transferring the sinusoidal motion of the swashplate to the fins. There are various ways to do this.
     
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