Halloween - Raven Animatronic

I have always been fascinated by haunted houses and dark rides ever since and loved making decorations for our Halloween parties. But I always wanted to make something that moves and makes sound - so I built my first ever fully automatic animatronic: a talking raven bird that sits on a shelf and greets our party guests.

I started with doing rough sketches and made some basic designs in 3d. At this point I was having no idea yet how to do solve the electronics.

Used electronic boards:

• Arduino Mega 2560
• Sparfun MP3 Trigger
• Polulu Maestro 12 Channel

I knew that the body had to be lightweight to not over stress the servo motors, and 3d printing was not an option for me at the the time. So I made the body parts out of plywood and paper. And the end of the board I built a control box for all motors and electronics.

Placing most of the motors outside of the bird and connecting it to the moving parts with bowden tubes gives me easy access to all motors - only the small motor for the beak had to fit directly inside of the small head.

I did not use any real feathers but used polyamid to give him a black feathered dress, that was flexible enough for movements.

The electronics have their own "deck". They feature an Arduino Mega, a Sparkfun MP3 Trigger for playing sounds from an SD card and a Polulo Maestro servo controller. A four line display shows me stats of the program and helps to set settings.

Two passive infrared sensors and two ultrasound sensors feed the Arduino with informations of movement to sense people around the animatronic. I pre-tested and animated the sequences of motion, lights and sound in Adobe Flash at 12.5 frames per second and than uploaded the animations into my own little engine on the Arduino. Every 80 ms it processes the next letter out of the strings and converts into commands for moving the body and the beak in sync with the sound and lighting effects.

I wrote several sequences that include random motion (looking around), specific motion patterns and saying sentences (lip sync). There is a physical switch to turn the talking to normal crow/raven sounds and a potentiometer to control how often it talks and makes noise.

Building the stage for the Raven in the basement - a stone wall for the Raven to sit on top and look down on the mortals.

I am very grateful that such accessible micro controllers like the Arduino exists and that there are so many helpful people that make great tutorials and share their knowledge online. I hope you like the project and I am looking forward to your feedback.