Dynamometer Performance Modeling and Experimental Assessment

Piezoelectric dynamometers are generally used for force measuring. During transient period, their performance is limited because the signals they delivered are distorted by their dynamic behavior and then are different from applied force. This paper proposes a method to identify the dynamic characteristics of the dynamometer so that the distortion of the signal can be compensated leading to the actual force. This method is based on the interrupted cutting of a specially designed workpiece that provides a strong broadband excitation. The three components of the exciting force and the acceleration of the gravity center of the dynamometer cover plate are measured simultaneously. Although the input acceleration components are correlated in the frequency bandwidth of interest, the nine terms of the dynamometer transfer matrix are determined from only one cutting experiment. To assess the developed method, series of different pulse excitations are carried out. Then, the determined transfer matrix is used for dynamic cutting force compensation under some milling operations. [S0022-0434(00)01003-0]