Aim: In this paper, the authors present a novel design for an instrumented handle to be used in the measurement of the grip force exerted during hand-arm vibration test (specifically hand vibration transmissibility tests). The handle - compliant with recommendations from ISO 10819:1996 and ISO 15230 - has been instrumented using two miniature load cells installed inside the handle. The paper will report on the design and calibration of the handle, also in relation to the present state of the art for grip force measuring handles, and it will describe its vibrational characterisation. Method: The novel design is realised using two semi-cylinders and 2 miniature load cells between them. Full compliance with the ISO 10819:1996 recommendation has been imposed in the design phase and a numerical analysis of the vibrational behaviour of the handle has been carried out before its realisation. Finally the instrumented handle has been statically calibrated and experimentally characterised for its vibrational behaviour. Results: Good linearity of the force to voltage response of the instrumented handle has been obtained from the calibration tests. Experimental vibrational analysis has shown no resonances in the ISO 10819 M spectra (16-400 Hz) while only one handle resonance is present for the H spectra (100-1600 Hz) with a reduced effect on the acceleration measured on the handle. Discussion: From results obtained, it has been shown that the handle is correctly measuring grip according to ISO 10819:1996 definitions. Calibration test performed have reported for the grip force a measurement range of 200 N and uncertainty of 0.12 % f.s.. From the vibrational point of view, the handle can be used for transmissibility tests in both ISO 10819 recommended spectra .
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