November 09, 2017 by Muhammad Aqib
Make this weather station — including your own anemometer and rain gauge — with a base model Raspberry Pi.
A few months back, I was wondering how weather stations work. How do they acquire and display data? I decided it would be a great IoT project to make.
I did a little research and found some commercial systems I could base mine off, as well as some online tutorials to help with some of the sensor or Raspberry Pi concepts.
This is a complete Raspberry Pi weather system with just the base Raspberry Pi hardware, camera, and some assorted analog and digital sensors to make our measurements. No buying pre-made anemometers or rain gauges — we are making our own!
Features:
All of the software for recording and displaying the information is on Github and is open source.
This project was a great learning experience for me. I got to really dive into the capabilities of the Raspberry Pi, especially with the GPIO, and I hit some learning pain points as well. I hope you can learn from some of my trials and tribulations.
The main enclosure houses the PI, the camera, the GPS, and the light sensor. It is designed to be waterproof, since it houses all the critical components, and the measurements are taken from the remote enclosure, which is designed to be exposed to the elements.
Enclosure contains:
This is where I stored the temperature, humidity, and pressure sensors, as well as the hook ups for the rain gauge, wind direction, and wind speed sensors.
It's all very straightforward. Pins here connect via the ethernet cables to the required pins on the Raspberry Pi.
I tried to use digital sensors where I could, and any analog are added on to the MCP 3008. It takes up to 8 analog, which was more than enough for my needs, but gives room to improve/expand.
This enclosure is open to the air — it has to be for accurate temperature, humidity, and pressure. The bottom holes are popped out, so I gave some of the circuits a spray of a Silicone Conformal Coating spray (you can get it online or a place like Fry's Electronics). It should protect the metal from any moisture, though you have to be careful not to use it on some of the sensors.
The top of the enclosure is also where the wind speed sensor fits. It was a toss up — I could have put the wind speed or wind direction on top, but I didn't see any major advantages of one over the other. Overall, you want both sensors (wind direction and speed) high enough so buildings, fences, and other obstacles don't interfere with the measurements.
I mostly followed this tutorial on Instructables to make the actual gauge.
I made this out of plexiglass. Overall the plexiglass worked okay, but combined with the glue gun, rubber sealant, and overall cutting and drilling, it doesn't stay looking pristine, even with the protective film.
Key points:
This was simple. Key Points:
The software is also open source and is available on the same GitHub repository.
Software is written in Python to record the data from the sensors. I used some other third-party Git libraries from Adafruit and others to get the information from the sensors and GPS. There are also some cron jobs that pull some of the API information. Most of this is explained in the Git documentation at docs/install_notes.txt.
The web software is in PHP to display it on the webpage while also utilizing YAML for the config files, and, of course, the RRD tool to store and graph the data.
It utilizes the Weather Underground API to get some of the interesting data that sensors can't pull. Record highs and lows, phases of the moon, sunset and sunrise times, and tide information is also available on their API.
All of it is available on GitHub, and is actively maintained and currently being used as I further refine and calibrate my own system, so you can submit feature requests and bug reports as well.
The software changes themes depending on the time of day. There are four stages. If the current time is plus or minus two hours from sunrise or sunset, the sunrise or sunset theme will display.
