Actions
Forum Thread Details
  • Replies 2 replies
  • Subscribers 391 subscribers
  • Views 530 views
  • Users 0 members are here
Related

Controlling a sewing machine with the PWM output from GRBL Arduino shield?

vindieselwalker

The foot pedal on the sewing machine is a 0-5V 400ohm POT. Wondering if there's any way I can control that with the PWM output. Hoping to control the speed of the stitch as if it were the spindle speed of the CNC.

End goal is an automated quilting machine.

Parents

  • It could be a potentially dangerous and expensive adventure - gotta keep an eye while experimenting and hopefully don't make any mistakes with the code!!! Runaway sewing machine ahoy! No responsibility accepted for any damage either, just general advice:

    • If you've determined the input is 0-5V derived from potential dividing using a potentiometer in the pedal, you could in theory share a common ground with the Arduino and run the PWM through a resistor/capacitor style filter to smooth out the PWM into an analog voltage - the downside is that there will be some lag in the control and you wouldn't be able to quite stop it straight away.
    • If you can handle just full speed or stopped, you could just run the unit from a digital output that gives either 0V or 5V. But that's in the ideal case - in reality, there will be some non-zero voltage at logic zero, and maybe slightly less than 5V at logic one. But you might also add a resistor in-line in case of logic clashes to avoid causing any damage in case of overcurrent in the circuit.
    • This would only really work in case of the control current being relatively limited. But if the sewing machine isn't isolated from the mains, probably not a good idea to common the grounds, you might need an optoisolator or similar.

     

    - Gough

Reply

  • It could be a potentially dangerous and expensive adventure - gotta keep an eye while experimenting and hopefully don't make any mistakes with the code!!! Runaway sewing machine ahoy! No responsibility accepted for any damage either, just general advice:

    • If you've determined the input is 0-5V derived from potential dividing using a potentiometer in the pedal, you could in theory share a common ground with the Arduino and run the PWM through a resistor/capacitor style filter to smooth out the PWM into an analog voltage - the downside is that there will be some lag in the control and you wouldn't be able to quite stop it straight away.
    • If you can handle just full speed or stopped, you could just run the unit from a digital output that gives either 0V or 5V. But that's in the ideal case - in reality, there will be some non-zero voltage at logic zero, and maybe slightly less than 5V at logic one. But you might also add a resistor in-line in case of logic clashes to avoid causing any damage in case of overcurrent in the circuit.
    • This would only really work in case of the control current being relatively limited. But if the sewing machine isn't isolated from the mains, probably not a good idea to common the grounds, you might need an optoisolator or similar.

     

    - Gough

Children
No Data