This is totally off topic, but I thought a few of you might get a chuckle out of the prototype “harmonograph” I just built. I had built one as a kid from plans in Popular Science magazine & got the urge to put one together again. So I threw this together in a couple hours, as can be seen by the quick & dirty construction, but I wanted to get the rough dimensions checked out before I built a nicer model. A quick Google search will reveal many other configurations based on a similar concept of “pendulum power”.

http://www.youtube.com/watch?v=fqzdggeFaiQ

http://www.youtube.com/watch?v=X0lEDZjxeIw

What aovely toy. A sort of funfair Foucault’s pendukum. I want one. :zbeer:

Somewhere out there… in cyberland… some engineer is busy at his machine writing the code to duplicate the movements of the weights/arms. I can hear him say…“Who needs gravity, we can write a program that does the same thing.”

Where will it all end…

:zbeer:

You are all too correct Larry. Many people find the cyber experience to be more appealling than the “real thing”. Here’s the mathematical formulas as described at:

http://local.wasp.uwa.edu.au/~pbourke/surfaces_curves/harmonograph/

x(t) = Ax(t) sin(wx t + px) + As(t) sin(ws t + ps)

y(t) = Ay(t) sin(wy t + py)

Why are we fooling around with actually building & sailing boats, when we could be sitting in front of a computer playing with a numerical model?

That’s neat Bill. My first thought was “This guy has too much time on his hands”. And then the darned device appeared to draw a Footy hull. Keep at it. You’ll have an organically designed Footy ready for next season. :zbeer:

And while on Youtube, I found this related toy. Way more fun that a simulated version.

http://www.youtube.com/watch?v=3TJKl9ZvbaI&NR=1