Are you looking into these creepy animated eyes…or are they looking into you?

These peepers were inspired by a concept by David Boccabella (Marcwolf) on the Stan Winston School of Character Arts forums. David is creating servo-driven animatronic eyes with a small OLED screen to simulate a dilating pupil. I'd chimed in with some suggestions and code to boost the refresh rate. Taking it to the next level here, we can render the entire eye…this makes the overall project simpler, as animatronics can be very fussy work (and the noise detracts from live performance).

UPDATE: This project was originally designed with the PJRC Teensy 3.1 or 3.2 microcontroller board in mind. Since then, the code’s been expanded to support many Adafruit boards: most Feather or ItsyBitsy boards with the “M0” or “M4” designation (not AVR or 32u4 boards), plus HalloWing M0, and Circuit Playground Express with the optional TFT Gizmo. For the HalloWing M4 and MONSTER M4SK boards, we have a more evolved eye project.

Most of the documentation and diagrams here proceed with the Teensy 3.2 in mind. With a pinout diagram for one of the above boards, it’s usually straightforward to adapt.

This is a “choose your own adventure” project. There are many ways to build it…this guide is not really aiming toward any particular finished thing. It’s the start of a recipe, but where it goes is up to your imagination…

• Spooky eyes in the window for Halloween
• An amazing costume for Dragon*Con
• A single eye worn in a pendant or a bracer, or in the headpiece of a staff
• World’s creepiest taxidermy

Read through to see what parts are involved for different configurations.

Parts from Adafruit:

• PJRC Teensy 3.2 microcontroller (one board will control 1 or 2 eyes); Teensy 3.1 will also work. (As noted above, many Adafruit M0 and M4 boards can also be made to work.)
• Display(s) - one per eye: either 1.5" OLED or 1.44" TFT. OLED looks amazing but costs more. TFT is affordable but colors are less intense. Tradeoffs!

Additional parts and tools:

• Soldering iron and paraphernalia
• 28 gauge ribbon cable
• Optional: 1.5" Acrylic cabochons (half-spheres)
• Optional: 3D printer to make enclosures, held with #2-56 screws and nuts
• Optional: LiPoly Backpack and battery (500mAh for OLED, 150mAh for TFT)

The following components are OPTIONAL. Our software can handle all of these effects autonomously, but you can optionally add any or all of these parts to enable manual control:

• Analog joystick for movement
• Button(s) for eye blinks or winks
• Photocell makes pupils react to light

If using a PJRC Teensy board, this project requires the Teensy 3.2 (or 3.1) microcontroller (or one of the aforementioned Adafruit boards). Not the Teensy 2, 3.0, LC, nor any other Arduino-like board, period. It relies on features unique to ARM microcontrollers.

This project involves detailed soldering around costly parts; read through before deciding if this guide is for you. Newcomers to electronics might start with the Animating Multiple LED Backpacks guide — it achieves a similar effect with easier, more affordable components!