View Single Post
  #8  
Old 25-04-2010, 08:57 AM
kinetic's Avatar
kinetic (Steve)
ATMer and Saganist

kinetic is offline
 
Join Date: Jun 2008
Location: Adelaide S.A.
Posts: 2,292
Quote:
Originally Posted by ChrisM View Post
Steve, do you know the specs of your drives? ie. rpm & torque? I have calculated that I need a torque of around 3 - 5 Nm although incorporating a margin above that range is probably advisable. And I think a speed of around 50 - 60 rpm for the output shaft should translate into an acceptable dome speed. On the internet I found the CMG geardrive "sub-fractional" horsepower units which employ single phase 240 Vac motors.

To get traction, I am thinking that a soft rubber wheel might provide the necessary "grip" on the steel ring, but there may be other solutions.


Thanks for the tip Greg re Brett.

Chris
These are the two matching DC motor/reductions that I have in
mind for sharing the load via friction roller or winch or crown gear
type arrangement.
http://www.iceinspace.com.au/forum/s...&postcount=115
They have a DC clutch, DC motor and good , strong set of final
gears.The last gear has a positional encoder on it.
It might seem perfect for the job but a problem I see is if I use
this setup in a shared meshed arrangement, it is so strong that
any problem in one drive would cause the other to keep driving
and possibly destroy the dome base-ring. It's only plywood.

Steve
Reply With Quote