It's a teardrop skeleton covered in a stretch fabric. the traction cycle goes like this: an expandible ring grows from the front, stretching the fabric. It expands and rolls to the end of the teardrop, then colapses back and travels to the front to start the cycle again. there is always an expandible ring moving water. if the ring is wide enough, the fabric can make a "parachute effect" making this device to look kind of like a jellyfish.

in order to make this engine quiet, the force might be build on engines inside the submaine. wrapped on a Noise-cancelling wrapping.

This way you can have a silent submarine that doesen't revolves water with a propeller.
-- noyola, May 23 2009

So it's a sort of motorised watery maggot? Your best idea yet. +
-- xenzag, May 23 2009


(+)...but I dare you to fess up as to the inspiration.
-- 2 fries shy of a happy meal, May 23 2009


Without a tube around, this the device would be quite ineffcient. and as you have something physically moving from front to back (as oppposed to something virtually moving like in an undulating fish) you put a cap on top speed. This might be something for high viscosity environments (proven by maggots living in such, but no fish-like movers)
-- loonquawl, May 24 2009


Ew.

I know it's kind of pedestrian for around here, but wouldn't magnetohydrodynamic propulsion be so much simpler?
-- elhigh, Jun 01 2009


For that matter, wouldn't a tesla pump also be simpler (and still be quiet)?
-- goldbb, Jun 01 2009



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