Gaussian Fuzzy-Based IoT Prototype for Real-Time Milk Quality Monitoring and Automated Sorting
Rafiuddin Syam, Nur Hanifah Yuninda and Fathan Fatazka

Universitas Negeri Jakarta

Abstract

The quality of raw cow^s milk is highly dependent on dynamic parameters such as pH and temperature, which are susceptible to rapid changes during storage and handling. Manual inspection methods are often subjective, inconsistent, and lack real-time capability. This paper presents the design and implementation of an Internet of Things (IoT)-based prototype system for real-time monitoring and automated sorting of milk suitability using a Gaussian fuzzy logic approach. The system integrates a pH4502-C sensor, a DS18B20 temperature sensor, an ESP32 microcontroller, a BTS7960 motor driver-based conveyor actuator, and Firebase cloud platform for real-time data storage and remote monitoring. Measured pH values are first corrected for temperature using a pH temperature coefficient of --0.03\,\text{pH}/^\circ\text{C}-, then processed by a Gaussian membership function-based fuzzy inference system to determine milk suitability levels (Fair, Less Viable, Not Viable). Experimental results show that the pH and temperature sensors achieve relatively low error rates ranging from -\pm1\%- to -\pm5\%- compared to reference instruments. The fuzzy logic system demonstrates consistent performance with manual assessment, yielding an average pH difference of only 0.028 and defuzzification values that correctly correspond to each suitability category. The conveyor system responds accurately to fuzzy outputs, moving forward for acceptable milk and reversing for rejected milk. Real-time data transmission to Firebase enables remote monitoring via a mobile application. The proposed prototype offers an objective, accurate, and scalable solution for automated milk quality control, particularly suitable for small-to-medium scale dairy operations, while contributing to sustainable development goals (SDGs) in food safety and smart agriculture.

Keywords: Gaussian fuzzy logic- milk quality monitoring- automated sorting- Internet of Things (IoT)- ESP32- pH and temperature sensors- real-time system- BTS7960 conveyor- Firebase cloud- dairy automation

Topic: Applied Technology in Physics