[ExI] underwater sprinkler, was: RE: Musical instruments in space

[BillK]

On Sun, Mar 31, 2013 at 10:05 PM, spike wrote:
<snip>
> I have tried to derive those equations, and I have failed so far.  But if
> you manage to derive the equations of motion, I can show you how to solve
> them and make a controls system.  Then we can rig up a physical-world
> analog, test it to see if we know what we are doing, or if we are just a
> bunch of controls wannabes.  {8^D   If someone here manages the derivation
> and it turns out simple, I will be highly annoyed.  But I will get over it.
>
>

<https://en.wikipedia.org/wiki/Feynman_sprinkler>
Quote:
The smallness of the torque on a reverse sprinkler is closely
analogous to the propulsion of the so-called "pop pop boat," a toy
boat that moves forward as it alternately expels and then sucks in
water through a pipe connected to a small internal tank heated by a
candle.



BillK