The kaisatsuko is an electric experimental musical instrument invented by Yuichi Onoue of Tokyo, Japan.

The instrument consists of two strings on a fretless neck. A crank is affixed to a small nylon wheel mounted on the body. The player turns the crank, causing the wheel to spin and "bow" the strings. This concept is similar to that employed by the hurdy-gurdy. Unlike most hurdy-gurdies, Onoue's instrument has no keybox, but is fingered along the neck. This detail is similar to the dulcigurdy

Dulcigurdy

The dulcigurdy was an early music instrument, of unknown original name, of the hurdy-gurdy family, but distinct in that the notes were changed by fingering the neck rather than pressing tangent keys...

, a hurdy-gurdy variant recorded by Michael Praetorius

Michael Praetorius

Michael Praetorius was a German composer, organist, and music theorist. He was one of the most versatile composers of his age, being particularly significant in the development of musical forms based on Protestant hymns, many of which reflect an effort to make better the relationship between...

.

Besides the Kaisatsuko Onoue also developed an 24-TET quarter tone

Quarter tone

A quarter tone , is a pitch halfway between the usual notes of a chromatic scale, an interval about half as wide as a semitone, which is half a whole tone....

tuning on his guitar as well as a deeply scaloped electric guitar for microtonal playing techniques.