joystick mechanics

[Stopp,Gene]

If you have a way to cut and drill small metal brackets, you can make an
X-Y controller using long-shafted regular pots. I've seen a drawing of
it, and I'm confident that I could just build one up on the workbench if
I had to, so let me see if I can describe the method:

Take a long-shafted pot, mount it on a fixed bracket. Make a metal
bracket with another long-shafted pot mounted in it, and mount the
bracket onto the shaft of the first pot so that the two shafts are at 90
degrees to each other. Mount a long handle on the shaft of the second
pot, and that is your joystick handle. Notice that the first pot if
fixed, and the second one moves, so you'll need flexible wires going to
it. Some mechanical forethought in bracket design would ensure that the
axes of the pots intersect each other.

If you want to get a third dimension of control, replace the long handle
with a third pot so you have X, Y, and twist.

Did I describe that right? I don't even want to try ASCII graphics for
this one, Courier or no.

 - Gene

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From: Paul Perry
To: synth-diy at mailhost.bpa.nl
Subject: joystick mechanics
Date: Thursday, February 26, 1998 7:12PM

there is a mechanical way(?differential gears) to convert
a joystick motion to two separate rotary motions.... so that
someone with a joystick can use any pots they want....
but i don't know the way!!!!! where is the Radiation Laboratory
'Computing Linkages' volume when you want it? ;)

seriously, can I make this with standard mech parts?

paul perry melbourne australia