Establishing traceability from the Kibble balance

Purpose and goal

This project aims at establishing traceability from the force realisation provided by the Kibble balance currently under development by NPL and RISE, focusing on the necessary mathematical modelling for this traceability and how the measurement uncertainty propagates in these models. This includes accurate modelling of the gravity in the Kibble lab for precise conversion from force to mass and development of a new comparison scheme to establish traceability to the other mass standards.

Expected effects and result

Developing the mathematical models is of key importance when establishing traceability according to the new definition of the kilogram. The project is complementary to the already existing Kibble-project and seek to solve several challenges that remain after the Kibble-balance has realised the gravitational force stemming from the test weight. Consequently, this project will advance the pursuit of high precision kilogram realisation, which is in demand from the Swedish industry.

Planned approach and implementation

The project has three work packages. WP1 focuses on modelling gravity in the Kibble lab for accurate force-to-mass conversion. WP2 develops a mathematical framework for the traceability between the mass from WP1 and the stainless-steel standards that exists at the national laboratory for mass. Lastly, WP3 includes dissemination of the results.