Which musical instrument did Leonardo da Vinci design with strings and keyboard controls?

Leonardo da Vinci designed the viola organista, a keyboard instrument with strings.

Leonardo’s drawings show an unusual instrument combining features of a keyboard and bowed string instruments. Pressing keys would move rotating wheels or bowing mechanisms against strings, producing a sustained sound. The concept aimed to let one performer control the pitches and expressive qualities associated with bowed instruments.

Leonardo developed several versions during the late 15th and early 16th centuries, but no instrument built by him has survived. The idea was technically challenging because the bowing mechanism had to maintain reliable contact with the strings while responding to the keyboard.

The viola organista is not the same as an organ, despite its name. It produces sound from vibrating strings rather than pipes. Modern builders have created playable reconstructions based on Leonardo’s drawings, helping demonstrate how the mechanism may have worked.