CNC Mill Controlled by FPGA

The project illustrates the use of FPGA in order to control the steppers in a CNC mill.

A milling machine is the most popular cutting machine which can be driven by a controller known as CNC. There are 3 axes in a simple milling machine as compared to 4 axes or more in complex machines and each axis is controlled manually by a handle. A motor moves each axis on a CNC machine as the motors rotations are precisely controlled by a controller.

The continuous current (CC) motors and stepper motors are the two types of motor commonly used. Closed loop motion control is used by CC motors due to the mechanism that monitors the motor rotation which allows faster operation and efficiency although less precise and more complex. Open loop motion control is used by stepper motors as they are controlled by electrical pulses although there is a possibility of missing steps if driven too fast which makes them to be always used at conservative speeds.

To connect to the stepper controller, a PC uses its parallel interface where the stepper motors or steppers of the CNC mill are driven in turn.

Rest of the project