Hi,
Is it possible with the smooth stepper ethernet to use potentiometers or similar to control the feed?
No, it is one of the few shortcomings of an ESS, it does not have any analogue inputs. If you are desperate to have analogue inputs then get yourself
a PoKeys 57E as an additional data input board. A 57E has a number of analogue inputs. PoKeys has made its reputation as a data input boards, and only later exploited that
for CNC use.
Another alternative is to have two buttons, one causing the feed rate to increase and the other to cause the feed rate to decrease. This the ESS can
do without any additions.
is it possible to connect a MPG for axis movement?
Yes. The ESS has a total of 51 inputs and outputs. If you chose to assign ports two and three of the ESS as input centric, as I have done with my ESS, then you'll have
a total of 31 inputs. I constructed an MPG and it requires five inputs:
two inputs for A and B signals from the MPG
two inputs for the axis select, note I combined them digitally so the two inputs can uniquely identify four axes
one input for incremental/velocity jog modes.
Craig