Here I am, this time with a project more “useful” in a practical meaning than the previous ones: a device that warns you when you receive a new notify on your Facebook profile.
But looks also count, so our device will looks like an typical american mailbox: as the notify arrives, a little flag on the box is raised, as shown in the following picture:
When the user will connect to Facebook, and read the notify, the flag is lowered.
I want to specify that this is a prototype yet: in next post I am going to publish the final version, with a better structure and decoration then the current one.
Beside a mailbox-shaped case and, as usual, an Arduino board and wires, we will need:
- a servo;
- a 100uf capacitor.
These components must be connected in this way:
When a servo motor starts to move, it draws more current than if it were already in motion. This will cause a dip in the voltage on your board. By placing a capacitor across power and ground, you can smooth out any voltage changes that may occur. Be careful: the cathode, that’s the side with a black stripe down the side, must be connected to the ground, and the anode to power. If you put the capacitors backwards, they can explode.
The bar consists of a cut straw, fixed on the servo; the little flag is just a stapled piece of paper.
The hardware is done. As of the software, instead of the previous project, this time we need two programs: the first is the sketch, loaded on the Arduino, which purpose is to raise or lower the flag, depending on the data read from the serial port; the second instead run on the computer, and its aim is to connect to Facebook, check if there are new notifies, and tell to Arduino what to do through the serial port.
This is my implementation of the sketch, while this is the second program: I’ve decided to write it in Python because of its simplicity. In order to work, you need to install mechanize and serial modules on your computer.
Now, you just have to put the Arduino inside the box; make two holes, one for the power, and another one for the servo; and run the software.
See you in next post for the final version. Stay tuned!