Leonardo da Vinci’s musical instrument combining a keyboard with bowed strings was the viola organista.
Leonardo designed the viola organista in the late 15th century. The instrument used a keyboard to control strings that were sounded by friction from rotating wheels or bowing elements. In principle, it combined the finger control of a keyboard instrument with the sustained sound associated with bowed strings.
Leonardo produced several versions and sketches rather than a single finalized instrument. The surviving designs show his interest in translating one kind of human action into another: pressing keys could determine which strings sounded while a continuous mechanical motion supplied the bowing effect.
The viola organista should not be confused with a conventional pipe organ or a harpsichord. It was not known to have become a standard Renaissance instrument, and no authenticated original instrument survives. Modern makers have built reconstructions based on Leonardo’s drawings.