- Raspberry Pi B
- 8 GB SD Card
- 5V Power Supply
- 9V Power Supply
- Wi-Pi USB Wi-Fi Adapter
- C5478 Transistor
- F/F Jumper Wires
- Test Leads with Alligator Clips
- Flat Ribbon Cable (28 AWG or thinner)
- 5 Pin Molex (SKT)
- 5 Pin Molex (HDR)
- DHT11 Temperature/Humidity Sensor
- Small CPU Fan
- Small Plastic Container
- 6 Small Bolts
- 10 Corresponding Small Nuts
- Wire Cutters/Strippers
- Soldering Iron
DISCLAIMER: I am not an electrical engineer. Most of the stuff I cobbled together with a wish and a prayer. Please proceed with caution and at your own risk. And don't make fun of my crappy soldering.
The most important feature I wanted was a system that would try and maintain a set humidity level. That means if the humidity drops below a specific value it should start adding moisture until the specified level is reached and then turn off... and rinse, wash and repeat.
To achieve this a reservoir for distilled water was needed. I used a small plastic container I found at Walmart. This particular container had a plastic lid. The plastic lid worked out nicely because it made it easy to refill water and also easy to attach the necessary hardware. Another thing I thought of was to use some florist foam to keep the water from evaporating too quickly but I figured I could add that later. I really just wanted to get things going and tweak as needed.
|Small plastic container.|
The next thing I needed to make this "active" was to add a fan so that it could push moisture out of the container. Because the lid was plastic it was easy to drill some holes through it. Some holes were for ventilation and 4 holes were for the hardware to mount the fan. I "eye-balled" most of it so in the picture you'll see that I ended up using only 3 bolts. I chose to put the fan on the inside and oriented the fan so that it would "push" moisture out.
|Small DC fan mounted on underside of the lid.|
|DHT11 sensor mounted on top of the plastic lid.|
- see current humidity inside the humidor without opening it
- see current temperature inside the humidor without opening it
- see historical temperature and humidity data over time in some nice graphical way
- see if the fan was currently running
- see historical fan data - like duty cycle or something
- set the humidity level that I'd like to be maintained
- get notified when the water is low or needs refilling
- keep track of the inventory inside the humidor
- keep track of tasting notes for particular cigars
- share inventory and tasting notes with friends
This is the interface that I came up with. It's still a work in progress but has most of the stuff that I wanted. This was built using a Java REST web service running in Tomcat. The UI was written using GWT. The data shown in the charts is only for an hour or so. I started everything from scratch in order to take a screenshot.
In the next post I'll go over the setup of the Raspberry Pi and the wiring of all the components since that should be all setup before going through the software side of things.