[Dino] is about three-quarters of the way through his talking box project. He’s completed one of the two boxes, and is showing off the technique he uses to marry motion with sound in order to mimic flapping lips with the box top.
You may remember [Dino's] first look at the EMIC2. It’s a single-board text to speech module which is what provides the voice for the box. But what fun is that without some animatronics to go along with it? So [Dino] started playing around with different concepts to move the box top along with the speech. This is easier said than done, but as you can see in the video after the break, he did pull it off rather well. He built a motor control circuit that takes the audio output of an LM386 amplifier chip and translates it into drive signals for the motor. The shaft is not directly connected to the lid of the box. Instead it has a curved wire which is limited by a piece of string so that it doesn’t spin too far. It lifts the lid which is hinged with a piece of cloth.