In Part 1 of this, I went over the setup of ThingSpeak and several associated and almost-associated packages.

This part will be more about the funner stuff.

Rain Gauge Reader

The first thing I had to do was build a rain gauge reader.  I ultimately started that before doing part one, but then moved on to a standalone node.js program that counted clicks from the rain gauge.

The rain gauge is a tipping-bucket rain gauge that tips when the rain gets to 0.2mm.  The guts are in the picture below.

Rain Gauge Innards

These are the guts of the rain gauge. You can see the tipping bucket (black) and the barrier terminal that connects to the switch. Yep, that’s all it is, a switch.

The rain gauge initially came with a little board that has a PIC and an EEPROM that stored clicks.  I didn’t care for that idea, since the ultimate plan is to see if we can put this on our building’s roof with a battery and a solar panel.

This is where the BBB comes in.  I connected the rain gauge to the BBB and started playing with node.js until I came up with the program in the gist below.

Rain gauge connected to Beaglebone Black computer.

Beaglebone Black connected to the rain gauge. I routed the wires through the drain of the rain gauge, which may change when I actually put this in use.


After setting it up, it was time to test.

Chart showing rain in inches

Wow, it rained for a half inch during a minute in my office!

The third part of this will be making this fault-tolerant: fixing the time issue (it doesn’t keep time), starting things during startup, and security.

-73-


Category: Beaglebone

About the Author

Andrew is the owner of this blog and enjoys computer programming, building things, and photography. He's a pretty busy guy, which explains why updates to this blog are so infrequent.

2 Responses to BeagleBoard Black WX Station Part 2: Node.js+a rain gauge

  1. Brett says:

    Have you completed this project? I am interested in building a all-in-one IP rain gauge that reports directly to weather underground. This appears to be very close. I am interested in contacting you about this project.

    • Andrew says:

      I haven’t had the chance to do much with it except for working on getting a little temperature/humidity sensor working on it (with so far, no luck). The BBB is not really powerful enough to run ThingSpeak, and I’m concerned about the disk space as well. Whenever I get back to working on this, I intend to move ThingSpeak to a real web server and have the BBB send rain, temperature, humidity, windspeed, and wind direction (assuming I can find or build a anemometer/wind vane).

      Feel free to drop me an email at ke8p (at) ke8p.us if you have any additional questions.


This is the new server