Abstract:
Humidity monitoring in the cargo holds of bulk carriers is a critical aspect of
maintaining cargo quality and supporting the efficiency of the loading process. The
manual monitoring methods previously employed have significant limitations in terms
of data continuity, accuracy, and operator dependency, often resulting in delayed
detection of environmental changes within the cargo hold. This study aims to design and
develop a prototype Smart Maritime Cargo Monitoring System based on the Internet of
Things (IoT) using an ESP32 microcontroller and DHT22 sensor as an automated and
real-time atmospheric monitoring solution for the cargo holds of bulk carrier MV.
EVRYDIKI. This study employs a Research and Development (R&D) methodology
based on a simplified Borg and Gall development model, consisting of four main stages:
needs identification, planning, system design and prototype development, and testing
and refinement. The developed system integrates a DHT22 sensor to measure
temperature and relative humidity, an ESP32 microcontroller as the main control unit, a
buzzer as an early warning alarm, and a web-based monitoring application accessible
via smartphone or computer in real-time. Test results demonstrate that the system
operates with an average error rate of 1.9%, well below the 5% industry tolerance
threshold. The system also proved capable of detecting humidity anomalies and
automatically activating the early warning system through two simultaneous alert
channels: an acoustic buzzer installed in the cargo hold area and push notifications sent
to the Officer on Watch's device. The system classifies cargo hold conditions into three
categories: "NORMAL", "CAUTION", and "DANGER". Validation by expert lecturers
in the fields of Nautical Science and Instrumentation, along with 20 Nautical Science
cadets who had completed sea service, yielded an accumulated feasibility percentage of
96%, placing the prototype in the "Highly Appropriate" category. The Smart Maritime
Cargo Monitoring System prototype is therefore declared fit for implementation as an
effective and sustainable cargo hold environmental monitoring tool aboard bulk carrier
vessels.
