This is the first year in a while that I am not matching my kids in costume. They are Mine Craft theme this year and I just can't pass up the opportunity to do an improved version of my maternity Halloween costume from 11 years ago. I mean, it's not every year I am 7+ months pregnant at Halloween.
When I was pregnant with my oldest child back in 2006, I tore off a dolls head and stuck it to my belly and covered it in blood. You can see it here https://www.instructables.com/id/gruesome-maternit...
It was a great costume and drew lots of looks but I wanted to it better this time around.
This year we are using a creepy demon baby head and adding a servo to top it off. And I already had most of the stuff I needed from previous projects.
You will need:
a creepy doll (got mine at Spirit Halloween)
cardboard (always save this stuff)
arduino uno with computer cable
bread board with jumper cables
8 AA battery holder with on off switch (I reclaimed the one I used on our Monado from a few Halloweens back https://www.instructables.com/id/The-Monado-Shulks...)
4 AA battery holder with on off switch
12 AA batteries
DC power barrel male plug connector
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Step 1: Attach Servo
Take that wicked doll and remove its head.
I didn't care for the hair since I wanted it to be more like a new born so I also removed the hair. I was just held on with glue so it was pretty easy.
Chose one of the attachments that comes with the servo to use. I chose the x shaped one. Screw it onto the bottom of the doll head.
Then you can attach it to the servo.
Step 2: The Base
Now we need a base for the servo to sit in to hold it still and a way to wear this base around the stomach.
Get some card board and trace the bottom of the servo.
Draw an oval around the tracing. I wanted to try to make it kind of look like shoulders so it would make sense under my shirt.
Cut out the tracing of the servo from the center. Cut the oval out.
Use it to trace several more. We need enough to cover the servo up to the tabs near the top.
The last oval should not have the servo hole cut, you should dig out a layer of the cardboard to make an indention for the servo sit in.
I was using thick water heater box card board so it took 5 ovals for me.
You also need a solid oval to use for the base to sit against the stomach.
To be able to wear this, I decided to use a belt. So we have to make a channel in the base to slide the belt through.
I traced the oval and drew 2 lines across the center length wise. The width between these lines should be the width of the belt you are using.
Cut out the 2 ends of the oval this makes. My belt was thick so I had to make 2 of these.
Step 3: Glue
Stack your pieces in order and begin hot glueing them together.
Should be from the bottom: the solid oval, the belt channel pieces, the oval with the indention, then all the ovals with the holes.
Slide the belt through the channel.
When you are happy with the set up, you can secure the servo in place. Using either screws from the top of velcro in the hole or even hot glue.
Step 4: Try the Fit
Try it on and make sure it works for you.
Step 5: The Code
Being that it has been a long time since the last time I worked with coding an Arduino, I struggled with this part.
I looked all over for pre-made code to make the servo turn a random degree and at a random interval. I could not find this.
After trial and error and alot of research, I finally was able to make the servo turn a random amount but I couldn't figure out how to make the delay random. I ended up just coding it a variety of delays myself.
Plug your arduino into the computer, make sure you have the arduino program, and load the code.
From the servo, plug the yellow wire into pin 9 on the arduino, the red wire into the 5V pin, and the black wire to the ground pin.
Run the code and make sure the head begins to move. If its all working, you are ready to set up portable power.
Step 6: Make It Move!
Here is where all the electronic stuff comes in.
It has been a long while since I've done anything with the arduino. I had to look it all up again.
I used these 'ibles to help:
Definitely go check those out and follow them to get the wiring explained better.
Basically we are plugging the yellow wire from the servo into pin 9 on the arduino,
run a black jumper cable from the ground on the arduino to the ground (blue side) column on the bread board.
plug the power from the servo to the power(red side) column on the bread board
plug the ground from the servo to the ground column on the bread board
plug the power from the 4 AA battery holder to the power column of the bread board
plug the ground from the 4 AA battery holder to the ground column of the bread board.
Wrap the exposed wire of the power from the 8 AA battery holder around the exposed wires of the power og the Barrel connector and cover the connection with electrical tape.
Wrap the exposed wire of the ground from the 8 AA battery holder around the exposed wire of the ground of the barrel connector and cover the connection with electrical tape.
Plug the barrel connector into the arduino.
Turn on the power switch to both battery holders and watch the head begin to move. If it doesn't move, check your wiring and try again.
Get something to hold all the electronics in to wear. I was given a little fanny pack from a friend that worked perfectly.
Step 7: Last Steps
You need a sacrificial shirt to wear. Cut a small hole in the shirt where you want the head to go.
I made the hole smaller than the head because I put on the cardboard base with the servo under the shirt and attached the head from over the shirt.
Doing this exposed the bottom of the head and a little of the servo so I used some scrap black fabric and hot glued it the doll head around the neck. Then to put on, you push the fabric skirt through the hole in the shirt and then attach the doll head to the servo.
I found that the head periodically pops off while we are walking. I'm not sure if it's because the fabric gets bunched up under the head and pushes it up or just the way it is hanging off to the side on the servo. I eventually ended up just super gluing the attachment on the doll head to the head of the servo. This solved the problem and it lasted the whole 2 hours of trick or treating.
Thanks for checking out my 'ible and hope it was helpful.