How can i control this stepper motor ?

[albertzeng]

Now, i happen to design a winding machine using some old instruments.I have a DC motor and a stepper motor.what's more, i must control the distance between each coil, so i use a stepper motor to feed and DC motor to wind.Then, the two motors must cooperate with each other, that's to say, DC motor rotate once, stepper motor has to feed a certain distance, and i use a speed sensor too.
The question is how can i control the stepper motor, and i don't know what kind of speed sensor is proper, how to use the singal from the speed sensor to control the stepper motor.

 

[Grossel]

It depends of type stepper. Whitout providing more details this is the help ypu got.

The speed censor must be of type tachometer, but you must feed the output signal to the µcontroller directly rather than convert it to DC voltage.

 

[albertzeng]

I have planned to use a two phase , bipolar hybrid stepper motor. I greatly care what i should measure from the pulse singal of the speed sensors so as to control the stepper motor, what's more, the DC motor and the stepper motor can cooperate well.

 

[Grossel]

i must control the distance between each coil, so i use a stepper motor to feed and DC motor to wind

This is the very source of problem I think. If you draw a simple drawing I might understant how you're going to mount your stepper. Will there be control of angle or do you want to control distance?

Are you going to use two cogwheels or you going to use a rack and pinion solution?

As stated before - to measure movement of DC motor you need a tachometer to it's main drive shaft. Unfortunately I doesn't know the name of the plate with holes around it's outer edge. And you of course need an optical censor.

 

[albertzeng]

here is the whole mechanical model of my problem

 

[Grossel]

Here's a general solution:
1 - Make a basic circuit for moving the stepper fourth and back.
2 - Count cycles from start position to end position.
Now, the distance the stepper will go will be:
distance = total_length * current number of cycles / number of cycles between start and end position

 

[albertzeng]

Hi, Grossel, i got it, thank you!