Modeling mechanical vibrations by the use of impedance measurements

Mechanical vibration models facilitate the calculation of complicated struc tures. Instead of the simple one-mass-model a more precise description of t he real situation is possible with a four-pole circuit and a terminating-im pedance. The difficult measurement determination of four-pole parameters ca n be substituted by a simple impedance measurement. From the impedance func tion given as a rational function and by development in a continued fractio n the equivalent circuit can be determined. Then the four-pole parameters a re calculable. The effort for the measurement is transferred to the calcula tion. The so obtained model enables a better understanding of the frequency behaviour of a mechanical system.