This video shows a stepper motor used as a servo motor. Pretty simple, I'm just showing it to share the idea.
The video has subtitles.
It doesn't appear that you're using any sort of positional feedback on that stepper motor, which doesn't really make it a servo. Still a nice demo, and a good use of salvaged printer hardware (I have two old printers in storage just waiting for me to get around to tearing the goodies out of their guts).
That is correct. Without electrical feedback based on the motor's movement and/or position, then it cannot be correctly called a 'servo' motor and not capable of close loop control, rather it's just a stepper motor, used in open loop control. The OP is 'simulating' a servo motor in appearance but lacks the self correcting capablity of a true servo loop. For example if he keeps the pot at the same position, and then takes the motor shaft and manually forces it to a different position, over coming the magnetic 'cogging' torque, does the stepper return to it's original position? If it was a true servo loop it would.
Lefty
I understand your point.
I didn't know the technical difference. I even thought about using a kind of encoder to verify the position, but didn't succeed. I didn't know, though, that it was required to call it a servo.
I apologize for the mistake, and I will clarify that on the video description.