Underwater cultural heritage, such as ancient shipwrecks and submerged archaeological sites, faces increasing risks from climate-driven environmental changes. Salinity shifts, temperature anomalies, and biofouling contribute to the degradation of these resources [1]. This study explores deploying two IoT-enabled devices with a crowdsourcing strategy to monitor and address these challenges effectively.
The first device, designed for divers, measures pressure, temperature, and salinity during underwater campaigns and can be placed on the seabed for long-term data collection [2]. The second device, used by local communities like fishers and diving centers, is deployable from boats to 2-3 meters, capturing salinity, temperature, and chlorophyll concentration. Each device incorporates a data logger built on a microcontroller, connected to sensors via robust serial interfaces such as RS485. This configuration ensures reliable communication and minimizes signal degradation in challenging underwater conditions. The microcontroller interfaces with sensors to record measurements, storing data locally until retrieval. Both devices feature a power management system with custom-designed PCBs for efficient energy use.
Data gathered by the devices is stored locally and transferred to a cloud platform via an intuitive mobile app. Communication between the devices and the smartphone uses Bluetooth Low Energy (BLE), while data uploads to the cloud via LTE. This simplifies retrieval and reduces the need for complex equipment or infrastructure.
Community participation plays a central role in this system. Local communities deploy and retrieve boat-based sensors, improving the coverage and frequency of monitoring activities. By pooling data from various contributors, detailed information of environmental conditions near cultural heritage sites is acquired.
The devices undergo rigorous calibration to ensure reliable data collection. Conductivity sensors are standardized with salinity benchmarks, temperature sensors tested with laboratory-grade instruments, pressure sensors calibrated in controlled chambers, and chlorophyll sensors validated using fluorescence references.
Field trials at two underwater sites tested the system under diverse conditions, providing a robust environment to assess device performance and crowdsourcing effectiveness. Feedback from divers, local participants, and heritage professionals refined functionality. Adjustments included stronger enclosures, improved BLE connection stability, and an enhanced mobile app interface.
This study demonstrates the potential of combining smart sensor technology with community engagement to protect underwater heritage. Leveraging IoT devices and collaboration expands monitoring, reduces costs, and fosters local stewardship, offering a scalable, sustainable solution to mitigate environmental impacts on submerged cultural treasures.
References:
[1] P. Michalis, C. Mazzoli, V. Karathanassi, D. I. Kaya, F. Martins; M. Cocco, A. Guy and A. Amditis, "THETIDA: Enhanced Resilience and Sustainable Preservation of Underwater and Coastal Cultural Heritage," IGARSS 2024 - 2024 IEEE International Geoscience and Remote Sensing Symposium, Athens, Greece, 2024, pp. 2208-2211, doi: 10.1109/IGARSS53475.2024.10642229.
[2] L. Pavlopoulos, P. Michalis, M. Vlachos, A. Georgakopoulos, C. Tsiakos and A. Amditis, "Integrated Sensing Solutions for Monitoring Heritage Risks," IGARSS 2024 - 2024 IEEE International Geoscience and Remote Sensing Symposium, Athens, Greece, 2024, pp. 3352-3355, doi: 10.1109/IGARSS53475.2024.10641101.
Acknowledgement:
This research has been funded by European Union’s Horizon Europe research and innovation programme under THETIDA project (Grant Agreement No. 101095253).