I’ve just developed this glockenspiel using the Arduino tool chain and ESP32. A 32 note glockenspiel with wired and BLE MIDI. I made the first prototype, then the final, repeatable version. PCBs sourced from PCBWay in China.
Very neat device - its just asking for a demo with "Flight of the bumblebee" 
I found another
such glockenspiel on youtube that had an actual robotic stick over every chimebar, making a
very unwieldy version that you couldn't play by hand.