Motors

[pavankukkala]

Hi ,
Why servo motor rotates only 180 degrees and stepper motors only 360 degrees?

 

[Martaine2005]

They don't. Servo motors by definition are motors. The servo itself might have a stop or limit.
As for why steppers or any motor ONLY rotate 360 degrees is beyond me!

 

[Colin Mitchell]

Servo motors are actually a box with a shaft at one end. The shaft connected to a gear box and the gearbox is connected to a 3-pole motor. You connect an arm (or lever) to the shaft. The arm then pushes or pulls to activate something via a rod. The arm does not rotate fully one complete revolution because it does not have to. The arm only has to rotate half a revolution to create push-pull on the rod. That's why it rotates a little more than half a revolution.
A stepper motors goes around and around and around. But you make it go around by sending a pulse that only increases the rotation by a few degrees. You have to keep sending pulses to eventually make it rotate a complete a revolution.