Kibble balances compare the weight of a mass with an electromagnetic force, allowing mass to be measured from fundamental constants instead of a physical artifact.

The NIST story focused on KIBB-g2, a small tabletop Kibble balance designed to make high-accuracy mass measurement more practical outside large national labs.

I developed the diagram directly from a CAD model provided by the researchers. The final image shows the instrument scale and labels the parts needed to understand the mechanism: mass pan, optical encoder, electromagnetic coils, magnets, and flexures.

A short GIF isolates the flexure, showing how the thin metal structure bends in one direction while restricting unwanted motion.