GatorByte - An Internet of Things-Based Low-Cost, Compact, and Real-Time Water Resource Monitoring Buoy

Abstract

Conventional water resource monitoring systems are usually expensive, have a low-temporal resolution, and lack spatial dimension entirely. These systems are typically available as stations or handheld devices. Pinpointing sources of pollution using these systems can be difficult. This project involves developing a high-resolution free-flowing monitoring buoy that records spatiotemporal water-quality data in flowing stream environments. The system is highly customizable, and even users with limited experience in programming or electronics can tailor GatorByte to their needs. The platform includes a data logger, a cloud-based server, and visualization tools. The data logger uses low-cost sensors, electronic peripherals, a 3D-printed enclosure, and printed circuit boards, with a total cost per unit under $1,000 USD. The data logger uses an NB-IoT-capable Arduino for real-time reporting and visualizing sensor data. The GatorByte records physiochemical water metrics - pH, temperature, dissolved oxygen, electroconductivity, and the current location of the buoy using a GPS module. The data logger also includes micro-SD storage and a Bluetooth module for on-field diagnostics. Using the GatorByte buoy, the collection of variations in water quality data in temporal as well as spatial dimensions can be achieved cost-effectively and reliably, enabling quick detection and resolution of pollution events.

Keywords: Environmental Internet of Things; Low-cost sensors; Physiochemical water quality monitoring; Spatiotemporal water quality monitoring; Urban water quality monitoring.

Graphical abstract

Fig. 1

Platform Overview – Overview of the GatorByte platform and its components that includes the sensors, actuators, data locations, and communication systems.

Fig. 2

Buoy dimensions and survey illustration – The image on the left shows a GatorByte buoy’s 3D printed housing and its dimensions. The small form factor allows deployments in narrow or shallow waterways. The illustration on the right shows two GatorByte buoys surveying water quality in a stream.

Fig. 3

Hardware CAD illustrations – a) 3D models of the pH, EC, DO, and RTD sensors in their sensor adapters, b) the bottom enclosure showing the holes where sensor adapter thread in, slots for the PCB and the battery, c) the enclosure lid with holes for screws and T-slot for an optional solar panel attachment, d) the sensor probes attached to the adapters, e) an assembled buoy bottom enclosure with all the electronics, sensors, and battery. The enclosure is sitting on a 3D printed stand. f) The lid enclosure that attaches on top of the bottom enclosure with four metal screws.

Fig. 4

Microcontroller hat CAD illustration – The microcontroller hat schematic houses various electronic components, the microcontroller, and the universal GatorByte interface to connect to the sensor baseboard PCB.

Fig. 5

Sensor baseboard CAD illustration – The sensor baseboard schematic shows footprints for sensor interface ICs and connection terminals, the stalk PCB interface, and the universal GatorByte interface where the microcontroller hat plugs in.

Fig. 6

Stalk PCB CAD illustration – The stalk PCB houses the reed switches and the RGB indicator LED. This PCB connects to the sensor baseboard via the stalk PCB interface.

Fig. 7

Sensor interface wiring schematic – The illustration above shows the sensor wire connection schematic. The wires are color-coded per their physical appearance.

Fig. 8

Guided calibration process – The image above shows the intuitive and easy-to-follow calibration instructions baked into the GatorByte’s firmware library.

Fig. 9

CAIP survey data visualization –Map and charts showing the data from the water quality survey at CAIP, Gainesville, FL, USA.

Fig. 10

SWB survey data visualization –Map and charts showing the data from the water quality survey at SWB, Gainesville, FL, USA. The blue lines show the data reported by GatorByte, while orange show the data collected by Hydrolab HL4 sonde. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)