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Having built a simple single-eye mechanism in the past, I wanted to improve on the design as well as making it more accessible to the maker community. The updated assembly uses parts that can easily be bought online, and almost all the components can be printed easily without supports. Designing the model in this way does sacrifice some functionality, but I’ll be releasing an optimised design in the future. This project is ideal if you want to build a functional and realistic eye mechanism, but don’t necessarily have access to tools like a lathe or speciality components.

Another feature of this design is that it’s designed to use snap-in eyes which can be replaced, and used with other 3d printed components to cast a highly realistic dome over the painted eye. This process is quite involved so I have another instructable on how to make the eyes, but if you’d prefer to use simple 3d printed eyes you can do that too.

This project will require some post processing of your prints, including some (hand) drilling and sanding, but other than the basics (3D printer, craft knife, screwdriver, Allen keys) there are no special tools needed.

Materials and Components:

3D Printer Filament: PLA is fine although I’d recommend you use a good brand because some parts are quite small and fragile. ABS is good for making realistic eyes but not necessary.
6x SG90 Micro Servos
Various M2 and M3 screws although any screws roughly that size should work ok.
Arduino: This design was tested using a genuine Uno, but it’s likely that any board which has SDA/SCL pins, 3 analogue inputs and a digital input will work. Arduino Uno
Servo Driver Board: I opted for a 16 channel PWM driver board from Adafruit
5V Power Supply, around 4A is more than enough. Here is mine (

A female DC power jack to match your power supply, to be soldered to the servo driver board

Jumper Cables
Potentiometer (10k ohms is generally a good value to use)
Momentary switch(Some joysticks have this built in, but its easier to control when its seperate)
10k Resistor”

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