Small Drive

[Robin Hewitt]

If it is battery powered then a stepper is a poor choice. An ordinary electric motor will take a big swallow of power to get you up to speed, draw peanuts to hold speed, draw nothing to slow you down if you use it as a brake. A stepper will draw the same regardless and eat your battery.

When you use a bog standard DC motor for positional control it gets called a "servo motor". The best DC motors, ie: most efficient, are the rare earth motors from Maxon. Less efficient motors are lots cheaper but you will need more battery and they make crummy brakes.

Speed is directly controlled by the voltage applied, positioning requires an optical "chopper" disc on a shaft somewhere.