Raspberry Pi Environment Monitor

I follow Raspberry Pi on Twitter and one day they posted a link to this site.  Some students from Westminster College have posted full details on how to connect some sensors to your Raspberry Pi to monitor such things as air temperature, barometric pressure, humidity and gas levels. Full credit to them. Brilliant!

They posted full details of how to build one so some eBay purchases, some soldering, some breadboard action and some Linux commands later I had a working one of my own.  The instructions are ace, it was pretty much paint by numbers with only a few minor tweaks.  Here's an image:

Key components I used:

• MCP3008 Analogue to Digital Converter
• DHT22 Humidity and Temperature Sensor
• BMP085 Temperature and Barometric Pressure Sensor
• A Light dependent resistor
• A variety of resistors and jumper wires (male to female)

Using the AirPi you can upload measurements to COSM, (see my previous posts), so I'm now measuring pressure, humidity, light levels and temperature and uploading all measurements to COSM feed 104017.

So I can use this to annoy my wife, (e.g. when at working asking "why is it 21 degrees at home, turn the heating off").

I have a de-humidifier at home so it's interesting to see the impact of this, (and show it's not just a noisy consumer of electricity).  Here's an image:

So the humidity cycles up and down over the course of the day and then at 2045 I whacked up the dehumidifier fan level and lowered the desired humidity level.  You can see the quick drop off in humidity.  It works (the dehumidifier that is!).