SELF MADE PROJECT
Mini version of working CNC prototype that uses two stepper motors and one servo motor. It has control software on PC that reads SVG files and then proceeds to calculate path of all motors and sends that to Arduino over USB.
It uses Arduino microcontroller and steppers that I scavenged from CD-ROM, for stepper driver I used any Darlington Pair I could find (TIP120 based ones) which have internal resistors and fly-back diode, each wire of stepper is connected through resistor to 12V, and Darlingtons are just connecting it to ground when needed which makes certain coil 'closer' to ground. Servo is lifting the pen up and down.
I redid the hardware part, implemented L298N stepper driver as well as 1N4007 diodes as flyback protection for driver. Driver has connection to logical voltage and +9V which reduces current it draws, and it wastes about two times less energy than my last circuit.
Control software is implemented now, uses SVG for drawing and calculates positions which are then passed to Arduino and then to motion, steppers are now in half-step drive and PCB is printed out, it is "shield" type so it's mounted on Ardunino