I am a big fan of The Matrix movie franchise. I was young when the movie came out and from then on I was hooked to Sci-Fi genre. So when it came down to my graduation, I wanted to have a Matrix themed cap. I mean the monologue of the movie suits well for graduation, isn't it? Unfortunately, when I googled I couldn't find anyone who did a Matrix themed cap (No Matrix fan out there???).

Being an Electrical Engineer I wanted to incorporate electronics too. I brainstormed from the LED matrix display to LCD. But all those seemed either too complicated or overkill. After a couple of days of hair-pulling, this is what I ended up with.

Its very simple. I was accoladed by many and it was featured on Arduino's official website (YaY!).

Step 1: Electronics

Let's start with the electronics. Checkout the video for the animation i created with Adafruit's Neopixel Ring LEDs. I used one 16 RGB LED Ring and one 24 RGB LED Ring. It is highly recommended that you follow Adafruit's Neopixel Tutorial to understand how these LED Rings work. My code is the modified version of the Adafruit's Neopixel Example code.

Schematic:

I used Arduino mini Pro (3.3V - 8MHz) to minimize the power consumption. This board doesn't have FTDI chip, so in order to upload the sketch you will need FTDI Breakout. The lithium battery provides 3.7V and it should be connected to 'RAW' pin of the Arduino not 'VCC' pin. The 'GND' is connected through a SPST slide switch, so that I can turn ON/OFF accordingly. The reason behind the 1000uF cap and 470Ohm resistor are explained in Adafruit's tutorial. With two Neo Pixel Rings we have 40 LED in total (24+16). Arduino's digital pin 6 is connected with the outer ring's (24 LED Ring) 'Data input'. So LED1 to LED24 will be in this ring. LED25 to LED40 will be in the inner ring.

Although I used different color wires in the schematic but in practical I used black thin wire that blends well with the graduation cap.

Step 2: Matrix Digital Rain

Now it is time for the Matrix Rain. I wanted to have a static rain to keep things simple. I googled for some wallpapers. The ones I ended up using are attached. But you can go wild. Choose what suits you best. There are literally thousands of matrix wallpapers. Print out the designs with a good color printer.

Step 3: Cut(!) the Rain!

Cut along the red lines as shown in the first image. You get the idea. Choose the ones that you want to have on your cap. It doesn't have to be single lines. You can even cut 2-3 lines together. As the cap is black, the background of the 'rains' will blend with it.

For the monologue I used this font. These fonts might come handy too:

(a) Matrix Font 2 (b) Matrix Font 3 (c) Matrix Font 4

What I did was print the quote with three different sizes so that I can experiment what suits me best. I separated all the letters. That way I can have the control what goes where. I also attached another image where letters are together if you want to separate the words instead of letters.

I ordered the graduation cap from ebay. They are rally cheap!

I used Elmer's School Glue to attach those lines and letters on the cap. There is no design rule how you should do it. Do whatever suits you best. Just follow these simple rules.

1) Rings should be placed in the middle (circulating the button). So place some of the 'rains' there so that rings can be on top of those (check images).

2) 'Rains' should be on top of the wires. It is better to hide the wires as much as possible. Check image how I did it.

3) The circuit should be inside the cap. I taped the ckt and battery at one side of the wall. If you wear a graduation cap you will see that some part of the inside doesn't touch your head. That is your spot.

Step 4: Neo: the Protagonist

I don't know where I got this idea, but the idea of Neo standing with guns seemed like a great idea! :D

First, you need to cover up the LED rings. Place the ring on one of the Digital Rain print. Cut accordingly. Then place Neo figure on top of that, draw a line around the feet of Neo and cut a hole. I used glue gun (during a uber ride I met a guy who was a marketing lead of the first glue gun product!!) to attach that on top of the LED rings. Before you do so don't forget to put the tessel in.

Now put a lot of glue in the hole and place Neo on top of that (check images).