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Electronics => Electronics => Topic started by: z3ngew on June 05, 2013, 12:36:15 PM

Title: stepper motor detent position
Post by: z3ngew on June 05, 2013, 12:36:15 PM

Hello everyone,
I know that stepper motors can rotate in discrete angle following a the fed control pulses, but i have a question, if the stepper motor is energized, the detent position of the rotor will be discrete also, or it may be located in between of 2 steps.

Thanks in advance,
z3ngew

Title: Re: stepper motor detent position
Post by: jkerns on June 05, 2013, 12:48:40 PM

It will move and stay at discrete points. You can do full steps, half steps, or with some effort - microsteps.

http://en.wikipedia.org/wiki/Stepper_motor#Microstepping (http://en.wikipedia.org/wiki/Stepper_motor#Microstepping)

Title: Re: stepper motor detent position
Post by: z3ngew on June 05, 2013, 12:52:54 PM

I'm sry, i meant if the stepper motor is unenergized, its detent position will be discrete or not

Thanks,
z3ngew

Title: Re: stepper motor detent position
Post by: jwatte on June 05, 2013, 05:00:40 PM

The rotor of a stepper motor is unanchored when not energized, and could be at any arbitrary position. Once the stepper becomes energized, it will "snap" to some particular step position.
I highly recommend taking one apart and looking at it. It's just a bunch of coils around a permanent magnet rotor with specifically shaped ends to give the "step positions." It works a lot like a brushless DC motor.