Electronic – the difference between stepper motors and servomotors

servostepper motor

I am not sure I understand what the difference between a stepper motor and a servomotor is. Could someone explain this to me?

Also how do these motors behave when they are paused or turned off, do they have enough resistance force to hold something in position (say 1kg) or do I need to do anything special for that?

Which of these two do you think would be a better choice for an application in which I would like to have slow movement in small steps (i.e. I will need a very small step followed by a pause in that position and then another small step and so on, and I would prefer each steps to change by exactly the same degrees).

Context for this question: I want to create a timelapse rig that will pan and tilt a DSLR camera over a period of time.

Best Answer

While the other current answer to this question quotes a comprehensive enough answer courtesy WikiPedia, here is a simplified TL;DR:


Stepper motor: Moves in steps, with a fixed number of steps per revolution. Thus, controllable across any number of revolutions, in jumps of the step size.

Could be unidirectional or bidirectional. Each step is exactly the same number of degrees.

Holding torque is (relatively) high, and a reduced holding torque is sustained even with coils de-energized.


Servo motor (specifically, hobby servos): Moves smoothly from a "rest position" to a "target position", works to retain this position till control signal changes. No steps.

Inherently bidirectional, but inherently limited deviation range. Pure analog control is an option. Not necessarily linear control, though.

Holding torque is dependent on the motor being energized, unlike steppers.

Typical hobby servos will go from say -90 degrees to +90 degrees, or -170 degrees to +170 degrees. Multiturn servos will go from x revolutions deviation from rest in one direction, to x revolutions in the opposite direction.


For a pan/tilt controller, a stepper motor matches the description in the question, since smooth panning / tilting is not a requirement. If smoothing of the movement is required, then a high enough gear reduction on the stepper achieves that.