The tuner is intended to become visually and physically integrated with the instrument rather than appearing as a conventional plastic clip-on tuner.

The system consists of:

• A compact electronics section mounted against a relatively concealed instrument surface
• A flexible PCB tail that wraps around an edge or curve
• A visible LED array positioned where the musician can see it naturally
• A piezoelectric contact sensor that detects instrument vibration
• A microcontroller that estimates pitch and maps tuning error to an LED position
• A small rechargeable LiPo battery
• USB charging
• One or more buttons for power, mode selection, calibration, or reference pitch
• The visual behavior should resemble a restrained Knight Rider-style scanning indicator.

They say you can't tune a fish, but that was just a tools problem. Flex-o-tune can attach to katsuoboshi and hopes to enable the world's first katsuoboshi marimba.