Just to share some thoughts after reading this:

https://en.wikipedia.org/wiki/Stepper_motor


Also please be careful and be aware that there is risk of damaging things.


yes, after lots of tests i discover the polarity switching sequence
to make the motor spin continuosly in one direction or the other.
of course the method of using a metro for banging each pulse
runs into problems when going a bit faster and it completely 
collapse.

I understand the context, BUT, I think this will happen at some point on any stepper motor, high speed is not their “show”.


it could be really cool if it where possible to do the control
with an oscillator as Roman suggested but then how would 
you connect the 4 cables of the bipolar stepper?

Consider this a risk to the amp, do it with a low power one, probably with one of those inside little usb speakers.

Any stereo amp has 4 cables for the speakers, L/ground to one coil, R/G for the other. (needs polarity testing for the motor cables)

More on this:

I think you can get very useful data on how to control that specific motor if you think of both coils as Microphones, you can connect both coils to your soundcard(A), ch1/coil 1, ch2/coil 2, and start recording the audio that it produces when spinning it with your fingers (or spinning it with another motor at a constant speed).

You will get very precise waveforms to analyze (specially the shift between L/coil 1 and R/coil 2.)

(A) Be sure not to connect the motor to your normal Mic input (some sound cards have +5V on the ring of 3.5 mm stereo jack for the electret microphones)


is there a tutorial on how to drive steppers with the same
control you drive sound into a speaker?

Probably you write one : )



Mensaje telepatico asistido por maquinas.