Concept: P1ano

This is a simple musical keyboard:

The core idea is, that a distance sensor detects which key is pressed and the hub then plays this note.

This works as follows:

When no key is pressed, there is nothing in the path of the distance sensor until the other end of the piano. In this case, the hub does not play any note.

When a player presses down a key/lever, the other side of the lever rises into the path of the distance sensor. The hub takes the measurement of the distance sensor to decide, which note to play and plays this note.