Development of an Experimental Method to Estimate the Operating Force of a Hand-Held Power Tool Utilizing Measured Transfer Functions

Abstract

Hand-arm vibration syndrome (HAVS) collectively refers to diseases caused by prolonged exposure to intensive hand-transmitted vibration, which has been affecting millions of workers who use hand-held power tools. The force interacting between a hand-held power tool and the work-piece is valuable basic information in studying hand-arm vibration problems, however cannot be measured directly. An experimental method is developed to estimate this tool force by utilizing the input point impedance of the hand and measured transfer functions of the tool. The developed method is applied to calculate the tool force of a hand-held grinder and a circular saw to demonstrate and validate the method. Possible applications of the method to study hand-arm vibration or tool design are explained.