Introduction: Halloween Baby Indicator

About: I am a Software Engineer who likes to tinker with many different technologies. One motto I try to live by is " I can stop learning when I die".

My wife and I were trying to figure out what she could wear for Halloween. This brainstorming session was a couple nights before she needed it to needless to say I was a bit rushed. She came up with this idea of showing off how far along she was with the pregnancy the same way I had years before with a Tesla charging station.


-Arduino compatible board (I used a NodeMCU board)

-RGB Addressable LED strip



-Soldering iron


-Hot glue

Step 1: I Need 10 LEDs!

So I was running low on LEDs and all I could scrounge up were precut pieces I had used on other projects. To fix this I had to solder the pieces back together as you can see in the photo. I also soldered the power, ground and data wires which will be connected to the NodeMCU board.

Step 2: Changing States, Views of the LEDs

I took a button I had lying around (two pins). I cut some old computer cable, two strips each about a foot and a half long. I stripped the ends and soldered one end of each wire to a button pin. I then 3D printed this enclose I designed. It was measured for a different button design, which I found out the button was broken. Instead of reprinting a modified design I just held the button in place and hot glued it. I have attached the stl for the holder that I printed.

Step 3: NodeMCU Programming and Soldering

I used a NodeMCU board because that's what I had lying around. I first used jumper wires to test out the button and the LED connections. Once I had the code working correctly I soldered the wires tot he top of the board and then cut off the pins on the bottom of the board. I have attached the arduino code.

I admit this is a quick job so the soldering isn't pretty and I could have have desoldered the pins but I was rushed for time.

Step 4: Lay It All Out and Wrap It Up

So I marked out where the shirt would fall on my wife's stomach. I printed the battery cover, first few layers in black then manually switched the colors to blue. Once it was done I hot glued it to the shirt. Once the hot glue had hardened i turned the shirt inside out and hot glued the board and LEDs to the shirt. To soften the shape of the electronics board and not make the shirt painful when wearing I used this flexible foam material I had left over from when some furniture was delivered (i'll be honest not sure what it is but it's pretty strong and easy to use). I put that on both sides of the board and the back side of the LED strip. Once everything was all glued up I attached the battery pack to test it out.

I am very happy with the final result!!!

Halloween Contest 2019

Participated in the
Halloween Contest 2019