Physical Computing • 2021
E-I-E-I-O is an interactive educational toy designed for children aged 2–4 that helps develop listening, recognition, and fine motor skills. The toy takes the form of a farm where children sort animal figures based on the animal sounds they hear. The game begins when the child presses the doorbell on the farm. A lantern turns on and the roof opens, allowing all animals to be taken out. After the roof closes again, the toy starts playing the first animal sound. The child must identify the correct animal and place it in the fence. If the correct animal is placed, the roof opens and the animal can be returned to the stable. This process repeats until all animals are back in the stable, at which point a small melody plays and the lantern turns off. The animal identification system is implemented using four tactile switches with momentary action. Each switch is uniquely wired to the master microcontroller. By detecting combinations of button presses, the system maps pairs of switch activations to six unique animal identifiers. This approach allows the toy to distinguish between six different animals without embedding electronics in the animal figurines themselves. Instead, each figurine has a uniquely shaped base that mechanically activates a specific combination of switches when placed on the animal distinguisher button. The switch states are read by the master ATmega microcontroller and mapped in software to the corresponding animal sound. The prototype demonstrates how interactive technology can support early learning through play. The project involved designing custom electronics, building printed circuit boards (PCBs) with ATmega microcontrollers, and integrating sensors, actuators, audio playback, and mechanical movement into a fully battery-powered device. The physical design combines laser-cut wood with 3D-printed components and animal figurines, which were post-processed and painted to create an intuitive and engaging interaction for children.
Created by: Rikke Skjoldager & Frederikke Johansen