Grimmboy is an RFID music player designed for children

Children, like normal-sized humans, love music. But most music players are designed for adult dexterity and user interface familiarity, which makes them difficult for young children to use. For many parents, Amazon's Alexa and similar services are the answer, as kids can simply ask a device to play whatever song they want. But to give them a quieter way to play music and keep some control over what they can listen to, consider building the Arduino-based Grimmboy RFID Music Player for Kids.

Because Grimmboy is for kids, the controls are as simple as possible. There's a pause/resume button, volume dial and status light - that's it. To select a song, album, playlist, recorded story or any other audio file, the child simply taps one of the RFID cards on the device. The cards, which are laminated with attractive cassette graphics, contain MiFare Ultralight C RFID tags that the parent can program with four-digit track ID lists. Grimmboy reads the list of track IDs from the card and begins playing files with those IDs.

The three key components of this project are an Arduino Nano board, a DFPlayer Mini MP3 player module and an MFRC522 RFID module. Additionally, Grimmboy contains a TP4050 battery charger/booster module with an 18650 lithium battery. Any LED will work for the status light, the pause button is a standard momentary push button, and the volume dial is a 1K potentiometer. The DFPlayer Mini has a built-in SD card slot for storing songs and so everything works offline without an internet connection. The demo enclosure was made of wood, but parents can get creative with the project to create something suitable for their own children.