Stepper Motor Controller – USB interface
I just finished designing a Stepper Motor Controller (SMC) for a PCB Mill that I ordered. One requirement most SMCs have is the need for a real-time operating system running only the milling software. This is because each motor movement must be timed precisely to ensure an accurate rate of movement from the milling head. If other software is running, then the timing of the interrupts can be off resulting in errors on the mill.
Not wanting to use a dedicated computer, I decided to design a bipolar chopper controller for myself. The big difference with this device and other controllers is that you will be able to feed it g-code directly, and not worry about controlling the timing. The processor onboard will be able to deal with the timing requirements and it should work. Some features include :
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Send g-code directly via USB interface (linux/mac/winblowz drivers), does not require dedicated PC
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Software controllable current (chopper mode) (1.5A/motor max)
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3-Axis on small PCB (2.9″x2.2″)
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USB interface, powered off USB except for motor.
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Over-temperature monitoring
If there is any interest, I’m happy to release the designs to the public domain.