The NIST microforce realization and measurement project

The National Institute of Standards and Technology (NIST) has launched a five-year Microforce Realization and Measurement Project focusing on the development of an instrument and laboratory capable of realizing and measuring the SI unit of force below 5*10^-6 N using the electrical units as the link to the International System of Units (SI). As a proof of principle, a prototype electromechanical balance has been developed to allow comparisons between mechanically and electrically derived forces up to 300 (mu)N with a resolution of 15 nN. Results from force comparisons using 1-, 10-, and 20-mg deadweights are presented.