In preparation for the redefinition of the international weight unit kilogram, the German institute for metrology (PTB) and Technische Universität Ilmenau develop an industrial-suitable scale that can be calibrated without weight pieces.
pursued to achieve the goal of a kilogram definition based on natural constants: the Avogadro experiment, in which the number of atoms is to be determined in an almost perfectly spherical crystal of isotopic silicon, and the kibble scale (or Watt scale), in which the weight of a mass in the gravitational field of the earth is compensated by an electromagnetic force. In both experiments, the value of the Planckian quantum of action is determined so that both approaches meet on the target line. While the PTB mainly follows the path across the silicon globe, the US NIST and the Canadian NRC favor the kibble scale. However, in order to be able to offer both paths in the future transfer of the mass units to the industry, PTB, together with the Technical University of Ilmenau, launched the prototype development of a Planck scale (as an industrial variant of a kibble scale).
More information: www.ptb.de