Feedback for my machine

to get back on topic here the feed back loops need to have a way to correct for error and work together. i would think of it like this. closed loop steppers or servos are only a semi closed loop systems when that's all that you are using. the encoder only picks up what is going on with the motor. so with a servo or closed loop stepper motor it does nothing to correct for things like backlash or a screw winding up under load. that's where the duel loop feedback system picks up the slack with a linear scale on the load.

the best thing to do is keep things as tight as you can so the system is as stable as you can make it. but a duel loop system is fully closed as far as the system goes.

i have plans to try this type of system out just because it's a different approach to precision ground screws and high end components. the duel loop method seems to have some potential to make a more accurate machine with less expensive parts. i just like to see how stuff works first hand. so what i see as a learning project might not fit into everyone's master plan.

if the duel loop system works well i don't see why it could not be used for rotary motion as well? time will tell

Twizzlermill wrote:

You could think about driving the ball screw nut instead of the ball screw, then the quality of the machining doesn't really matter.

I did a quick test of rotating nut some years back, it went at 60m/m with a Nema23 motor and 2505 screw, wobbly but bloody fast!