An IoT General-Purpose Sensor Board for Enabling Remote Aquatic Environmental Monitoring

The ability to provide near real-time data (e.g., < every 15 minutes) on aquatic environmental conditions via remotely deployed sensors is a highly sought-after capability. However, cost and complexity are often significant factors that limit the spatial and temporal coverage of such monitoring systems. Most existing proposals are expensive, complex and/or are un-malleable for adaptation to other environmental sensing applications. This paper presents a simple and flexible open-source IoT (Internet of Things) electronics design for viable near real-time environmental measurements - specifically tailored to the rigors of aquatic settings. The system provides the minimal required functionality for reliable remote sensor readings with a focus on low energy consumption, renewal energy supply, plug and play deployments, and stability over time. The system development is driven by actual deployment logistics and constraints. We compare three revisions of the system/circuit and show how we aspired towards the aforementioned goals, whilst outlining the evolution of the design based on practical experience. A performance evaluation of the system is given in terms of functionality, stability, cost and energy consumption. The IoT platform is at the core of an affordable near real-time aquatic monitoring system that has been used in multiple water quality studies. The system has been adapted for use in other applications including water height monitoring and air dust sensing.