Skull With Realistic Animated Electronic Eyes (Perfect for Halloween!)

Turn your project into something... that actually looks back at you! 👀

Hi makers! This is the first video I ever made. At first, I was unsure whether to post this project on Instructables, because the video quality wasn't exactly top-notch. But in the end, I decided to share it anyway — I truly believe this project can spark some cool ideas and help others make it even better.

In this tutorial, you'll learn how to create realistic animated electronic eyes, perfect for your next Halloween project! Using a Seeeduino XIAO and two 1.44" displays, you'll build an interactive decoration that responds to light with the help of a photoresistor. These electronic eyes are ideal for Halloween props, cosplay, robots, or any creative build that needs a spooky, high-tech touch. Get ready to impress with an eerie, blinking stare that feels almost alive!

MATERIALS LIST:

➡️ Amazon Links:

Seeduino XIAO SAMD21: https://amzn.to/3SJKvxc

MP1584EN Voltage Regulator: https://amzn.to/3yyYUpc

1.44" TFT LCD Display 128x128: https://amzn.to/3M1uKyg

Plastic Skull: https://amzn.to/3WCPotj

Photoresistor: https://amzn.to/4dESxjk

26AWG Silicone Wires: https://amzn.to/3AfET7Q

1/4 Watt Resistors: https://amzn.to/3yxUI9j

Ribbon Cable: https://amzn.to/3YEzz7X

➡️ Aliexpress Links:

1.44" TFT LCD Display 128x128: https://s.click.aliexpress.com/e/_Dla3F6F

Seeeduino XIAO: https://s.click.aliexpress.com/e/_DCFRz2b

Voltage Regulator: https://s.click.aliexpress.com/e/_DFhqMaP

26 AWG Wire Spools: https://s.click.aliexpress.com/e/_DkDl3cR

1/4 Watt 56 Ohm Resistors: https://s.click.aliexpress.com/e/_Dm9NWc3

Photoresistor: https://s.click.aliexpress.com/e/_DdH7gCh

Male Pin Header - 2 pieces, 8 pins: https://s.click.aliexpress.com/e/_DcjI2eN

Female Pin Header - 2x 8 pins, 2x 6 pins: https://s.click.aliexpress.com/e/_DCUAhtr

3x7 Breadboard: https://s.click.aliexpress.com/e/_Dc6iaUD

JST 2-pin Connector - 1 piece: https://s.click.aliexpress.com/e/_DCd6I1T

9V Battery Connector: https://s.click.aliexpress.com/e/_DcGWH89

Heat Shrink Tubing: https://s.click.aliexpress.com/e/_DnNBhmt

On/Off Switch: https://s.click.aliexpress.com/e/_DE7r8VL

Multicore Dupont Cable: https://s.click.aliexpress.com/e/_DeaaeGF

JST XHP 2.54 Connectors - 2x 8 pins + 1x 2 pins: https://s.click.aliexpress.com/e/_DeQO5I1

Dupont Connector 2.54 - 2x 8 pins: https://s.click.aliexpress.com/e/_DldLv5B

These components can also be purchased in kits at a lower cost — just make sure all required parts are included in the kit:

Crimping Tool for Connectors: https://s.click.aliexpress.com/e/_DFW2NBT

➡️ 3D print file: Makerworld

➡️ Project documentation

➡️ Documentations XIAO SAMD21

➡️ Documentations Adafruit

1. Start by soldering only the outer pins of the headers on the Seeeduino XIAO. This helps in case you make a mistake—you can easily correct it before finishing all the soldering.
2. Secure the XIAO using a third-hand tool and complete all the pin soldering carefully. Be gentle to avoid damaging the board.
3. Mount JST connectors on the perfboard:
4. First for the left eye monitor
5. Then for the right eye monitor
6. Add a third JST connector for the photoresistor
7. Secure everything again with a third-hand and finish all the soldering.
8. Finally, solder the two female headers that will hold the Seeeduino XIAO onto the perfboard.
9. Complete all the wiring following the attached circuit diagram.

The XIAO operates at 3.3V, but we will use a 9V battery to power it.

1. Solder the battery connector to the input of the voltage regulator.
2. Solder a JST connector to the output of the voltage regulator.
3. Connect the battery to the input connector and the XIAO to the output JST.
4. Use a multimeter to adjust the output to exactly 3.3V using the screw on the regulator.

Prepare the 7-wire cables that will be used to connect the displays. Begin by carefully stripping both ends of each wire.

Then, use a crimping tool to attach the appropriate JST connectors to ensure a secure and detachable connection.

If JST connectors are not available, you can solder the wires directly to the display pins as an alternative solution.

Make sure all connections are stable and well-insulated to prevent malfunctions or flickering during operation.

To avoid connecting the LED pins of the displays directly to 3.3V, each display requires a 56Ω resistor between the 5V VCC pin and the LED pin.

If you don't have a 56Ω resistor, you can use two resistors in series to reach the desired value.

Carefully solder the resistors, ensuring the connection is solid, and trim any excess leads to keep the layout clean and avoid shorts.

Just like with the displays, solder two wires to the photoresistor and protect the connections with heat shrink tubing.

This light sensor will enable the electronic pupil to react to ambient light, making the eyes feel more realistic and responsive to their environment.

3D print the box to protect the electronic circuit and keep everything in place.

Add a power switch and secure it using hot glue, applying it only on the short sides

Carefully insert the assembled circuit inside the box, making sure all wires are properly arranged.

Finally, close the box with screws to ensure everything is held firmly in place.

Open the Arduino IDE and configure it to work with the Seeeduino XIAO.

Install all the necessary libraries and select the correct board: “Seeeduino XIAO”.

Inside the config.h file, you’ll find various eye style options that you can enable or disable based on your preference.

Once you're ready, upload the sketch to the XIAO and start exploring the different eye designs!

Cut your decorative skull in half to make the assembly process easier.

Mount the displays securely using hot glue, and hide the photoresistor among the teeth for a realistic look.

Once everything is in place, close up the skull, connect the circuit to your PC, and... enjoy the show!

Try pointing a light at the photoresistor — the pupil will shrink just like a real eye!

Additionally, enable the eyelid tracking feature in config.h for even more realism.

This project is just the beginning. The eyes can be used in hats, masks, robots, animated puppets... endless possibilities! Try different styles and share your results in the comments!

If you found this project inspiring or helpful, don't forget to leave a ❤️!