Digital PID-Based Control for a Low-Cost CNC Plotter Machine

This paper presents the development of a cost-effective Computer Numerical Control (CNC) system using an embedded microcontroller platform. The system utilises a Proportional-Integral-Derivative (PID) control algorithm, implemented on an ESP32 microcontroller, to achieve precise motion control of stepper motors. The design features a custom-built G-code interpreter and a user interface that supports both manual and automated operation. Experimental validation was conducted using a prototype CNC machine, demonstrating reliable positioning accuracy and smooth motion control. The results confirm that the proposed system offers a low-cost alternative to commercial CNC controllers while maintaining satisfactory performance for educational and small-scale manufacturing applications.