Construction and Design

We designed the basic box using the online tool Makercase and then laser-cut it out of 4mm plywood. To make the toy completely safe, we treated the wood with a certified toy-safe varnish. If you don't have a laser cutter at home, the base can easily be made out of regular cardboard or printed on a 3D printer.

We used our 3D printer and PETG filament to make the details – we printed holders for the lights and special diffuser lenses that beautifully scatter the light from the LEDs. Everything inside was secured with a hot glue gun, including the custom-printed protective case for the microcontroller.

Solderless Electronics

We designed the entire project to be as modular as possible and completely solder-free. The heart of our traffic light is the ESP8266 chip. We connected all the electronics on a classic breadboard. Power distribution is handled by an MB102 power supply module, and we used 5mm pre-wired LEDs that already have a built-in resistor.

Thanks to the connections using Dupont jumper wires, we can easily take the electronics apart at any time in the future without damaging anything, modify it, or recycle the components for a completely different project.

Power and Software

To avoid the aforementioned problem with built-in batteries, the back of the traffic light features a practical opening door. The resulting space comfortably fits a standard power bank (which we all definitely have a few of at home). When it runs out of juice, we simply swap it for a fully charged one.

The software side runs on ESPHome. After a quick programming session, we could start smoothly controlling our home traffic. We have to admit, though, that our little guy is currently much more interested in the colorful wiring and the toy's internals than the lights on the front. But for a future engineer, that's actually a great start!