19 years ago
rotary tank to study fluid motion. I have many questions and probably could have
few of them answered on my own but what the heck. I have no experience in
though I have experimented with brushed DC motors and PWM controllers.
Kalliroscope is a type of rheoscopic fluid used to study fluid motion.
on Kalliroscopes / Revolving Kalliroscopes
A circular tank about 6-8" diameter by 3-4" deep, is mounted to a shaft
by a suitable bearing block assembly. It will be filled with water and
other particulate matter, driven by a PC controlled reversible DC motor. The
tank could be
a cylinder, but prefer a hemiphere. The problem is finding a hemiphere that can
accurately to a shaft. Perhaps a metal spinning co. might have some leftover I
with, however haven't yet asked around. If I had to have one built, what would
be the ~
cost of a hemiphere, aluminum or stainless steel, 6" dia x 3" height with an
1" height vertical wall section, with a boss or mating surface at the bottom
allow accurate placement on a flange or shaft? I imagine the less TIR, the more
Wall thickness can be whatever is necessary given it only has to contain water.
stainless steel then it can be similar to a kitchen mixing bowl. Max speed is
rpm or whatever that doesn't cause the water to be thrown out of the tank.
Coupling the motor to the tank. Should it be belt driven, or direct using a
coupler? Thinking of low speed DC servo motors in the ~300-550 rpm range at
and perhaps they can be direct coupled? Or should I
higher rpm motor and reduce the speed thru a belt drive? Since tank rotation
reversed frequently, I'm concerned with backlash of a coupler. I've seen zero
couplers but would then have to adapt shaft sizes, unless there are some
different sizes on each end. But I guess it depends on what the motor shaft and
diameters happen to be. Now if I had one of those 7x12's...
Another thought (though seems insane) was using something like this:
the max rpm was I believe 63 rpm for this model. Other models go to about
220 rpm or
so but were not on sale. However I'm not at all familiar with servo actuators,
and if it
would be worth it/too much trouble to adapt. The controller is expensive. Seems
overkill at 25 lbs. and they refer to it as compact, which kinda strikes me
course what am I thinking - I'm talking about a 6" diameter tank on my desktop.
servo actuator of that type allow for programming a smooth change in velocity
trouble? What other smaller servos with bearings suitable for direct mounting
reasonable for this application? A surplus servo and controller would be ideal
but I need
help in finding the right one that won't cost an arm. Having one that can take
directly would save a lot of work.
All this just to have the ability to repeat the rotary motions in case a
pattern interests me.
I appreciate your help.