This Device, Hidden in a French Horn, Turns Sheet Music Pages
Steven Quinn built this Bluetooth Page Turner, which he can hide in his French horn's bell, for digital sheet music.
Your favorite rock band may have all their music memorized and many famous guitarists can't even read music. But most musicians, like those playing in orchestras, read sheet music as they perform. If you've ever been to a piano bar with a pianist that takes requests, this is why they can play just about any song — they're reading sheet music. Like those pianists, Steven Quinn reads digital sheet music when he's playing his French horn. To make it easy to flip digital pages, Quinn built this Bluetooth Page Turner that he can hide inside his horn's bell.
The French horn is a brass instrument that ends in a large, flared bell. Musicians can control the pitch of a French horn in many ways, including with their lungs and lips, with hand-operated valves, and with the position of their hand in the bell. That final technique is the secret to this device's operation. Because Quinn keeps his hand in the horn's bell, he can push the device's buttons without the audience seeing. With a simple press of a button on the device, Quinn can flip to the next page of sheet music through the ForScore app running on his iPad. If he accidentally flips pages too soon or flips two pages at once, he can push the other button to move back to the previous page.
The primary component of this Bluetooth Page Turner device is an Adafruit ItsyBitsy nRF52840 Express, which has a built-in Bluetooth adapter. It receives power from a battery pack through a small booster module. The ItsyBitsy and two tactile momentary push buttons attach to a ProtoBoard. Quinn designed the enclosure in Shapr3D and then 3D-printed it. It straps onto the user's hand, positioned on their palm where the user can press the buttons with their thumb or index finger. Wires run from that to the battery pack worn on the user's wrist under their sleeve.
Quinn programmed the Bluetooth Page Turner to appear as a keyboard when it connects to a device, like an iPad. The two buttons trigger buttons presses: the left and right arrow keys. Those activate a page turn in the ForScore app. But if you use a different app or want to use this device for another purpose, it is easy to change the sent key presses in the code.