This is a tiara that looks like the top part of the Tardis, the Doctor's spaceship from the TV show Dr. Who. It includes a blinking light at the top. I designed it to be worn with an outfit that looks like the rest of the Tardis, for a Halloween costume, but it could be used for any costumed occasion!
Step 1: Gather Your Supplies
Access to a 3d printer
Access to an Inkjet printer
Acrylic Paint and Paintbrushes
3M strips or other tape
Adafruit GEMMA v2 chip
Adafruit Flora RGB Neopixels v2 LED
Batteries and Battery holder with on/off switch
Conductive Thread and needle
(I bought the last three items as a kit - http://www.adafruit.com/products/1657)
Note - I think there are many substitutions someone could make if they needed to - a tiara could be made with paperboard/cardboard and a headband, the circuit could be soldered instead of sewn, and the sign on the front could be hand-painted. Get creative!
Step 2: Print the Tiara
I designed the tiara in CAD by scaling down the dimensions of the Tardis and curving it to a headband shape. I've attached the STL file, and my CAD file is available to the public on Onshape under the name "Tardis Tiara".
My tiara was 3D printed using the Formlabs Form 1 printer using the white resin, so that an LED could shine through.
After printing, you may need to use a fine sandpaper to smooth the edges where support structures were. As long as you start small, it should work well!
Step 3: Paint the Tiara
Before painting the tiara, apply a piece of masking tape to the top lamp portion of the tiara - that will keep that section white so that your LED will shine through nicely. Be sure to apply the tape very firmly!
I used dark blue acrylic paint with a medium sized paintbrush to paint my tiara. I found that two coats of my paint worked best. I covered all the front surfaces with an even coat of paint, trying to smooth out any obvious brushstrokes while the paint was wet. Then I waited for the paint to fully dry before applying a second coat.
After the second coat dries, remove the masking tape. If any paint seeped under the edge of your tape, you may be able to remove it with some water (a cotton q-tip may help) or with some fine sandpaper.
Step 4: Create the Police Box Sign
To create a section of the tiara that read "Police Public Call Box", I chose to create and print a graphic. (My handwriting is terrible!)
I had to do some experimenting with my file and printer to get the piece the correct size, but in the end I was able to get a printout that looked right.
I cut out the paper and figured out the centered position on the tiara. Then I applied some more of the blue paint to the back of the paper and applied it to the tiara. Make sure to get paint all the way out to the ends of the paper to keep it from peeling up.
Step 5: Prototype Circuit
To create a blinking light at the top, I used a circuit consisting of one LED (mine happened to be RGB, but a white LED will work just as well), an Arduino-based programmable chip, and a battery pack.
I connected the pieces together with alligator clip wires to ensure that I knew how the circuit should run.
If you are using the same Adafruit set that I used, the Ground on GEMMA should go to the - on the LED, Vout should go to the + on the LED, and one of the D pads should go to the in arrow on the LED. The pictures above show D1 connected, but when I laid out my circuit I ended up using D0.
Step 6: Program Gemma
I used a browser-based tool to program my chip, https://codebender.cc/ If you are also using GEMMA, you can use my code, which is attached.
I found that a 500 milliseconds on and 700 milliseconds off time looked pretty good.
Step 7: Create Structure for Circuit and Sew Circuit
I used a piece of paperboard (it happened to be a box for bar soap, but a cereal box or similar material would work just as well) as the support structure for my circuit. I cut it close to size, then traced the outline of the tiara to see how much smaller I would want to cut it down. I also traced my chip and LED. I positioned the LED on the tiara-facing side of my paperboard, and the GEMMA on the opposite side. I oriented them so that the three different wire routes did not have to cross.
When I was prototyping, I learned that it was a lot easier to sew onto the paperboard if I kept the piece larger and then cut it down later. I would recommend giving yourself extra room. I'd also recommend using a thimble.
Step 8: Attach the Battery Pack
Add the batteries to the battery pack, plug the pack into the power inlet of the GEMMA, and turn on the switch to check your circuit. If it works, great!
Tape the battery pack to the tiara (I used 3M strips). Make sure you attach the tape so that you can turn the switch on and off.
Step 9: Wear Proudly
Have fun wearing your new blinking Tardis Tiara!