Gobelins - Arduino workshop

Rototo, musical rotophone

The project

At Gobelins school, we participated to an Arduino workshop. The aim was to create a human-machine interface (HMI) using a rotary dial phone, those pretty retro phones. With the reverse engineering process, we connected the phone to a server to display things and play sounds depending on the number we dialed.


We wanted to create a musical discovery and awakening interface for young kids. We noticed that kids enjoy manipulating objects from everyday life, especially the phones. So we imagined Rototo, the rotary dial phone that playfully helps kids learning English and music instruments.

Demo & technos

We used a UNO Arduino card to connect the dial rotatory phone cables with the web server. We used the HTML5 audio API with JavaScript to get the audio amplitude and play sound. Node.js & Johnny five helped us to access the dial signals with the web server. We used Web sockets to send it to the computer interface in JavaScript. We also sent the audio amplitude to the Arduino led components to change the light intensity.

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