Design of Control Unit for CNC Machine Tool using Arduino based Embedded System

The present work is concerned with the design and development of Control unit comprising of the Digital Differential Analyzer Interpolator as the core element in controlling the motion in X and Y direction of the Computer Numerical Control machine. The Control unit designed contributes a little but significant step towards low cost automation. Software interpolators are designed for performing machining operations on the work by performing interpolated motion of cutting tool. The prototype CNC Machine tool is procured from the manufacturer of CNC Machines for performing the work. The Atmega 2560 microcontroller used in this work is provided with Arduino development board environment for designing the control unit. Three unipolar stepper motors are used for controlling the machine axes. The X and Y axes are interpolated for two dimensional interpolation. The Z axis is used to control the depth of cut but it is not interpolated. Electronic Industries Association Standard code of part programming is used for implementing the G and M codes. The paper also discusses the development of algorithm for interpreters and interpolators as well as the real time graphical simulation and design of driver cards for unipolar stepper motors. The Control unit is tested for linear as well as circular interpolation by performing actual machining on CNC machine.