Solar-powered, outdoor, wireless environmental monitoring with e-paper display.
Designed to operate year-round in an outdoor, marine environment, BeachDisplay2 is completely self-powered, operating completely unattended.
The system features integrated sensors to measure rainfall, internal and outside temperature, humidity, and atmospheric pressure. The large, 11.6" e-paper display is easily readable in full sunlight, and consumes minimal power. Display content and operating parameters are remotely reconfigurable. The system interacts with users through a non-contact IR sensor, allowing additional display pages or other functions to be loaded or executed on demand, while observing proper health and safety protocols.
The current configuration for BeachDisplay2 provides swimmers, beachgoers, watercraft operators and fishermen with easy access to the data that most affects their ability to safely enjoy life on or in the water.
The system is maintained through AWS IoT Core via MQTT. Data is managed through an AWS Dynamo database. It is available in two versions: WiFi and Cellular via LTE-M/CAT-M1/NB-IOT.
A new prototype has been built and is fully functional using live sensor data. The second round of display boards for the new 11.6" display have arrived from fab, populated and tested. Above and to the right is a picture of the main display (first round) with live data.
The main controller board has also been fabbed and tested. The design is now based around the Pycom GPY, enabling LTE-M and WiFi on the same platform. All code has been retargeted to Micropython. The controller features a solar maximum power point charge controller, LiPO battery charger, battery fuel gauge, e-Paper interface, SD card and multiple expansion interfaces.
I've also integrated an Optical time-of-flight sensor that acts as a non-contact interface to allow a second page to be loaded on deamnd.
The system also now includes WiFi AP mode and web server (via a local hw key) to allow local reconfiguration and display of system parameters.
I've added a CO2 sensor as well, to provide a local air quality measurement.
Finally, we (and by we, I mean 'I') are adding some modifications to the enclosure to integrate design changes to enhance ease of installation. At the top are some renders of the latest design.
BeachDisplay2 features an integrated low-to-no-maintenance optical sensor that measures local rainfall. Once an hour, the accumulated rainfall during the previous hour is captured, stored and analyzed. The system maintains a running list of the previous 72 readings. A running sum of the previous 24 and 48 hours is displayed and used to determine rainfall events as defined below.
The Maryland, Anne Arundel County Health Department offers this guidance:
Well, isn't that nice. To be completely honest, I probably wouldn't even bother to look that up if someone wasn't already doing it for me, not to mention that it's not the easiest rule in the world to interpret for the average beachgoer (or even for an engineer).
So, how do you know when this rule is in effect? What's a rainfall of 1/2 inch? And what interval is that measured in? In one hour? In 24 hours? AND how do I know it's "after the rainfall" so I can start the clock?
Also, you can see that there are two sources (Operation Clearwater, and the Anne Arundel County Board of Health) that take water samples and directly measure the bacterial count of the water. They only test roughly once every two weeks, but this is the most direct method to determine water quality. Both sources do not test year round, and both stop testing around the end of August. Since I have a direct view of the beach, I can guarantee you that people still visit (and get in the water) all times of the year and long before any authority is testing the water.