This instructable explains how I setup a Raspberry Pi to open my garage door using a smarthphone. While this has been done before, I thought I'd post my solution. This was my first hardware project and instructable ever and I'm sure I made some mistakes. So, when you find one let me know!
What we will be doing is turning the Raspberry Pi into a small web server. When you access the webserver from your browser of choice, you will have a big button that triggers the garage door via a relay. We will wire a very basic circuit to the Pi's GPIO pins and upload a website that triggers the circuit. When the relay is triggered, it closes the circuit hooked up to the garage motor and opens the garage.
Why would anyone want to do this?
Well, my garage door opener was broke and this was cheaper than replacing the other system. As an added plus though, you could wire up additional sensors and be able to make sure your garage is closed remotely if your were so inclined.
I consider myself pretty cheap, and I tried to keep the costs minimal. All of the items are available on prime.
1.) Raspberry Pi - Model A - $32
2.) Wifi Adapter - $10
3.) PSU - $5
4.) 5v Relay - $6
You will also need an sdcard >= 2GB and some wires, but I had extra of each.