Control a stepper motor with USB-6001

[macole1703]

Hi, I am a college student. I have a project of controlling a stepper motor. I have a CD-rom stepper motor and L298n from Seeedstudio as my motor drive. I try to drive this motor with labview and usb-6001. However, I do not know wire configuration between driver and USB-6001. There is no examples about USB-6001. Am I right on the track to control the motor?

[jordans]

Hi macole1703,

Thanks for posting a new thread for this question!

Using a 6001 will be a challenge for anything more than the simplest types of motion control. What types of moves does your motor need to make?

[Kevin45]

Hi Jordans,

Yes, it is big challenge to me. I want to rotate this motor clockwise and counter clock wise. I cannot find any ports which have PWM function like arduino. 

Can I use DAQmx to control the motor? I think that a stepper motor is able to rotate with pulse, so the motor might be controlled with DAQmx.  

[jordans]

You are correct, most steppers take step and direction commands in the form of square wave pulses. However, could you confirm what type of motor you are using? You mentioned it was a stepper, but if it is from a computer's CD-ROM then it is just a regular DC motor. This will change how you wire and control the motor.

I am assuming that it is a regular DC motor and needs to be controlled with PWM signals.(though similar problems apply with steppers)

The main issue with using the USB 6001 is that it can only generate constant pulse trains and not true PWM. This means that you cannot change the velocity over time. If you want to try you can connect your digital lines as PWM outputs, but the card is not designed to do that and it likely will not work well. 

[Kevin45]

Thank you for your response. what I want to do is controlling the motor with constant speed. And the stepper motor I have is from CD-rom drive.

I sadly say that I could not find the specification of this motor. 

[Brian__P]

Hi Kevin45,

I agree with what Jordan said. If you don't want to buy a new device, you can try using your USB-6001 to send a PWM signal to the motor. The white paper below has more information on this:

http://www.ni.com/tutorial/2991/en/

[Kevin45]

Thanks, Poteet.

 However, I cannot find PWM port in USB-6001. Is there any port to alter PWM port just like arduino?

If I want to use PWM, should I use VI diagram you give the link above?