I need help with a stitch regulator: The machine head can move in both the x and y axis at the same time and needs to control bothe the speed of the motor and the number of turns. The number of revolutions per/in of travel needs to be adjustable. Also the the speed of the motor needs to vary with the speed of travel. Current applications of this use encoders on the x and y axis and a DC servo for power. The machine movement is by hand and the the power is for the machine head. Anyone have any ideas?

Thanks

 

I get the motor speed varying with the manual advance to keep the stitch interval the same, but the number of turns is a bit hard to understand.

In the old days, a couple of servo amps would have run the machine head. The variable stitch length - if I understand the adjustable revs per inch properly - makes it harder. It might be easier approaching this with a microprocessor reading the X & Y encoders and controlling the motor speed through PWM.

Are you able to do the electronics and programming this will entail?

 

Ok so I didn't explain it correctly, the machine makes 1 stitch per revolution. It need to be adjustable from about 8 to 16 stitches per/in.

 

So the motor needs to speed up for more stitches and slow down for less stitches? I take it the X/Y is fixed?

 

OK as the machine is moved manually the speed will not be a constant, travel may be in both axis at the same time, as when making a circle, so there is input from both the x and y encoder, Yes the motor will need to vary speed to keep the stitch count the same as speed and direction of travel changes.

 

Do you have particular motors in mind/on hand?

If you're going with DC motors, you might consider an L298 dual full-bridge driver IC.

For rotary encoders, you might consider Hall-effect devices.

Stepper motors might be worth considering, but would have to be fairly large or geared down to provide the torque necessary (read:slow)

 

This device has been and is currently being built. but you know how it is I want to try it myself. Currently the best of these regulators are driving servo motors, these are small units as not a lot of power is required. I do have some pdf manuals on whats already out there.