Internet of Things Based Instant Liquid Level Monitoring and Control for Vessels

Instantaneous monitoring and control of liquid levels in ship tanks is vital for operational efficiency, vessel stability, and environmental safety. This study presents and evaluates the performance of an Internet of Things based prototype system designed for real-time liquid level management in maritime applications. The system integrates multiple ultrasonic sensors for level measurement, an ESP32 microcontroller for data processing and Wi-Fi transmission, and the Blynk mobile application for remote monitoring and pump/valve control. A local control unit consisting of an Arduino Uno, keypad, and LCD display provides redundancy and manual intervention with password protection. The study investigates system performance under static and dynamic conditions, especially in the presence of periodic mechanical and random manual vibrations. Findings show that using a moving average filter with optimized window sizes (e.g., 5, 7, or 9) significantly increases measurement accuracy, achieving over 99% accuracy in fill rate calculations under periodic vibration. Whereas random oscillations lower precision, increased filter windows increase stability, obtaining on average up to 98.6% accuracy. The results demonstrate the applicability of the system to reliable liquid level regulation on ships and show the importance of efficient signal filtering method to reduce vibration-induced errors, offering an innovative solution for maritime sector.