I have central air-conditioning in my apartment. It’s controlled by a remote, using IR signals to send commands to the A/C control unit.
As any decent geek would, I’d like to be able to control my A/C using other means (e.g., a smartphone).
The last part in the puzzle is making all the pieces play nice with each other, and finally accomplish the intended goal – Controlling the A/C at home with the smartphone from anywhere over the Internet!
How was that accomplished?
An always-on computer in the apartment is running a web server accessible from the Internet, serving an “A/C-control site” (screenshot above from Android smartphone). The site is developed with the Django web framework and Bootstrap front-end framework.
The controls in the web-app are associated with server-side Python functions, that pass the parameters to an RPC server that talks with the Arduino that is connected to its USB port.
The RPC server uses the Arduino to send commands to the A/C based on the parameters it received from the web-app, and uses the microphone to verify that the commands were transmitted successfully.
As usual, the rest of this post provides in-depth description of what I’ve done. The actual projects are available on GitHub (web-app project, and RPC-server project) for anyone to fork, clone, tinker and use.