07-22-2020, 07:58 PM
Thanks, Yuriy
The basic gist of my idea uses that hollow-shaft rotary encoder I asked about last week. I'm going to make an adapter that fits it to the crank handle shaft of my rotary table. The 90:1 reduction of the table, combined with the 3600ppr encoder, should give me single arc-second resolution (360° / ((3600ppr * 4) * 90) = 0.0002777° = 1 arc-second). Using the encoder on the crank handle (rather than driving it by the table directly) makes backlash a concern, and I'm going to use a keyed 1-way bearing (sprag clutch) to mitigate that by preventing me from turning the handle backwards.
I'll definitely post up when I've finished the build.
The basic gist of my idea uses that hollow-shaft rotary encoder I asked about last week. I'm going to make an adapter that fits it to the crank handle shaft of my rotary table. The 90:1 reduction of the table, combined with the 3600ppr encoder, should give me single arc-second resolution (360° / ((3600ppr * 4) * 90) = 0.0002777° = 1 arc-second). Using the encoder on the crank handle (rather than driving it by the table directly) makes backlash a concern, and I'm going to use a keyed 1-way bearing (sprag clutch) to mitigate that by preventing me from turning the handle backwards.
I'll definitely post up when I've finished the build.
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