Recent Trends in Low Force Metrology and a Feasibility Study for the Development of a Facility for Low Force Measurements

The SI unit of force is more accurately realized through calibrated dead weights and is linked to the international prototype kilogram or a dead weight force close to 10N. As there is a growing need for traceable, accurate measurements involving micro and nano forces, such mass based force standards do not remain practicable for realizing such low forces. In view of this, National Metrological Institutes (NMIs) have started developing their indigenous facilities for realizing the small forces in order to disseminate the same to the user industries. In this paper, we have discussed the recent trends in the emerging field of low force metrology. The efforts made at NPL to take force measurement capacity to fraction of a Newton are described. A newly designed frame used in a dead weight system for generating the lowest possible force step of 0.5N is reported. The feasibility studies undertaken to increase our capability in realizing small forces further to the mili and nano Newton ranges are also briefly described.