Stepper motors for robotics
Stepper motors are a class of widely used engines in many applications such as 3D printers or robotics. They convert an electrical pulse in a defined angular movement called steps. Their advantage is that they have a potentially high torque and are quite accurate.
There are 3 products.
The NEMA 17 unipolar/bipolar stepper motor (200 steps/rev) proposed here by Pololu has a holding torque of 3.2 kg.cm and can be controlled in two different modes by compatible stepper motor drivers.