Application of pressure mapping techniques to measure push and gripping forces with precision.

Gripping and push forces, also named coupling forces, have induced effects on the transmission of the vibration in the upper limb. The assessment of the vibration exposure with powered tools thus requires that these man/machine coupling parameters are controlled and monitored. To date, no reliable metrological systems enable their precise measurements. This study first investigated how much precision could be expected from the pressure mapping technique for the determination of coupling forces by means of numerical integration. Then a specific procedure was worked out and validated to instrument hand-held tools and measure the coupling forces with regard to the appropriate current standards. The proposed method was applied as a case study on an ordinary breaker and an anti-vibration breaker.