Quote:
Originally Posted by bojan
Ditto.
BTW, there is no need for this procedure (limit switch than back to predetermined position).
If stepper motor is de-energised from full step mode, it will stay there (if not moved by external force).
Your software just have to remember the last position (phase) it was in before power down. and it has to restore it before moving to a new position.
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Hi,
that is possible, but there is always the chance that it gets moved slightly when powered off or at transport, especially if it is friction driven like a 10:1 microfocuser.
so a proper initializing routine will ensure repeatable accuracy.
else other option is on power off, it parks at the home position and then turns off like inkjet printers.
I tested focusing using a bahtinov mask and a 10:1 microfocuser. i took images everytime i turned the microfocusing knob, and noticed that a half turn of the microfocuser was the minimum movement after which a change in focus is discernible. I didnt measure the linear travel though.
this switch comes with 0.25 to 0.5mm sensitivity and has different types of actuators like roller actuators.
http://australia.rs-online.com/web/s...&cm_vc=prev_au
else this reflective optical switch would be better as the electrical ones may have issues with conductivity over a period of time.
http://australia.rs-online.com/web/s...duct&R=2192634