For our younger readers: the Furby is a toy released in 1998 by Tiger Electronics and that saw tremendous success in the following years. Each Furby is a little animatronic creature that resembles the Mogwai from the Gremlins films, but more colorful. When first unboxed, they speak “Furbish,” but then transition to English. While they speak, they move their ears, eyelids, and mouths. The toy has long since lost its popularity, but that didn’t stop Roni Bandini from modifying one to recite Jorge Luis Borges quotes.
While Furby toys are often described as robots, that term would be a stretch. A standard Furby only has a single DC motor to actuate all of the animatronic movement. But a clever gear mechanism controls what moves. If the motor only turns a little bit, it will just move the mouth. It can then turn further to move the ears or eyelids. Bandini discarded the original control board entirely and replaced it with his own to produce sounds, so he just needed to gain control over the DC motor.
Bandini chose to use an Arduino Nano board with an H-bridge for that job. A limit switch tells the Arduino when the motor is in the home position. Then it can rotate the motor the appropriate amount for the desired animatronic movement. Mouth movement syncs with the audio, which comes from a DFRobot DFPlayer Mini MP3 player board. Any time an audio clip is playing, the Arduino will move the Furby’s mouth. To keep it from jabbering on all the time, Bandini added a PIR (passive infrared) sensor. That tells the Arduino when someone moves nearby so it can activate a quote.
The quotes come from Jorge Luis Borges, who was an Argentinian writer of great renown. Bandini kept the Furby in its skinless state, which is a little disturbing. But at least it has deep and philosophical things to say.