No question, the harmonic drive [don't let the name scare you] is the best route to go. ZERO backlash ZERO.. which is a big concern w/ worm gear stuff [which can hit zero if adjusted regularly to keep them there]
Harmonic drives also have high reduction ratios [100:1 is no big deal] which is also something you'll want for two reasons. 1. You'll want to be able to absorb large force numbers and yet have a reasonable drive size. 2 Positional accuracy. If you have a standard 200 step stepper w/ a 100:1 drive you can position the table to w/in 0.018degrees. If you had a 10 step micro step drive it'd be 0.0018 deg. [Now we all know micor stepping isn't that accurate.. but in theory]
If you had a 500 line encoder on a servo it'd be 0.0018deg.
Anyway, you get the idea..
Got any CAD shot's of the machine?? How big is it going to be when completed? Intended use?
Jerry
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JerryFlyGuy
The more I know... the more I realize I don't
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management) |