Does anyone know of a simple method to control the speed of a stepper with a potentiometer?
I have found the speedy stepper library for arduino but couldn’t get it to work yet, and maybe someone has a better idea.
I recently got an old sewing machine (built mid 50ies) which works like a charm, but can only go fast and even faster. Since I’m a beginner at sewing I’d like it to go slower. I’ve figured out the mechanical side, decouple the original motor from the machine (this is even a built in function for winding bobbins), replace the hand wheel with a 3d printed one which has a GT2 gear and use a belt to drive it with a nema17. This gives me a 5:1 reduction, so less speed and more power, plus the stepper motor allows to reduce the speed even further.
Now for the electronics side, I imagined something like build a simple foot pedal with a potentiometer, connect that to an arduino or similar board, which then sends step signals to an A4988 stepper controller.
Software side should be easy, read analog input, if it’s over a threshold start running the stepper, update speed continuously depending on the input.
Bonus idea for when I get this running: add a switch to change to single stitch mode. When the pedal is pressed down, do a single revolution (motor steps * microsteps * reduction ratio) at a fixed speed, pedal has to be released and pressed down again to do another stitch.
Let me know if you have a good idea, otherwise I’m continuing to experiment with the stepper libraries by Stanley Reifel
Edit: just found another library which might be better suited for this application: SpeedStepper library
Edit 2: Or probably even better suited: AccelStepper