CoPiino Humidity Control - Joining Raspberry Pi and Arduino

I recently came across a friend of mine. We talked about our recent projects where he finally told me about his basement which has very high humidity and is currently not that good place where you like to run projects.

This made us think about a new project idea: "develop a control unit for intelligent humidity regulation"

Of course it had to be something smart with RaspberryPi and WiFi, so we are able to monitor and configure all sensors and fan units by tablet from the living room :)

On the other hand we wanted to have a reliable realtime control that is not affected by network issues and still operates when the Linux OS is stuck.

That's why we combined an Arduino compatible board with a standalone processor and combined it with Raspberry Pi.

So this is how it all looks like. The main parts are

• CoPiino board from http://copiino.cc
• Raspberry Pi from http://www.raspberrypi.org/
• Power Supply 5V for the control stack Reichelt 5V Power Supply
• Power Supply 24V for the fan unit Reichelt 24V Power Supply

• The powerful and long lasting fan unit from RS Online

  • it should have sufficient power even when running low speed to reduce noise as much as possible
  • Hint1: Computer fans do not have the power to create sufficient back pressure.
  • Hint2: I tried a lot of fans - I suggest to choose the fan wisely
• Humidity Sensors HTU21D from SparkFun

We also needed a bunch of small parts

• cables (we used a roll of 25m CAT5 patch cable - cheap and twisted pairs for long distances)
• connectors
• bolts, nuts

Tools

• PC
• screwdrivers
• drilling machine
• pens
• wire cutter
• soldering iron

Now its all about

• preparing the case for the control unit (including holes for the connectors)
• prepare the big case for the fan unit
• prepare the small cases for our humidity sensors
• prepare the cables (including soldering the connectors)

I do not have a screenshot of my tablet so I used the one from http://copiino.cc

CoPiino provides a Web IDE package that can be installed on RaspberryPi. It includes an apache web server and all required libraries for the CoPiino board which is stacked on top (as HAT) of the RaspberryPi.

Programming can be done from anywhere having WiFi access to RaspberryPi. So we basically needed to prepare the hardware first and then sat back and enjoyed programming the CoPiino board from the couch :).

The source code we used can be downloaded here:

• download: source code @ bitbucket.com
• or the link below

We will add more software pictures and sensor/control log data after running one month :).

Thanks for reading!