Traceable Calibration and Demonstration of a Portable Dynamic Force Transfer Standard
In general, the dynamic sensitivity of a force transducer depends upon the mechanical system in which it is used. This dependence serves as motivation to develop a dynamic force transfer standard, which can be used to calibrate a working transducer "in situ." In this work, we SI-traceably calibrate a hand-held force transducer, namely an impact hammer, by using a mass suspended from a thin line which is cut to produce a known dynamic force in the form of a step function. We show that this instrument is a promising candidate as a transfer standard, since the dynamic sensitivity has small invariance between different users. This calibrated transfer standard is then used to calibrate a secondary force transducer in an example application setting. The combined standard uncertainty (k = 2) in the calibration of the transfer standard was determined to be less than 0.71 % up to a bandwidth of 5 kHz. The combined standard uncertainty (k = 2) in the performed transfer calibration was less than 4 % up to 3 kHz. An advantage of the transfer calibration framework presented here, is that the transfer standard can be used to transfer SI-traceable calibrations without the use of any SI-traceable voltage metrology instrumentation.