As microprocessors and power electronics progressed, the control of brushless servo motors also became commonplace. Today, brushless servo motors have over-taken stepping motors in a wide variety machine automation applications.
So, are stepping motors still a viable choice for automated machines? In short, the answer is, ‘Yes!’
Stepping motors provide very reliable operation, long life, and are inherently stable and precise. They are usually operated open loop (without position feedback) which works well in most applications since they do not require feedback for precise control and positioning. They are relatively simple devices.
If a selected stepping motor is rated for the speed and torque that an application requires and, if the inertia of the motor’s rotor is a good match to the reflected inertia of the mechanism it will drive (called the “inertia ratio”), then a stepping motor may be a very good and economical choice.