Broadband dynamic parameters measurement by longitudinal vibration testing using pulse wave

Paper presents a method to measure the dynamic parameters of viscoelastic material bar by the longitudinal vibration testing in a wide frequency range.In the measurement,one end of the bar is driven by a transducer using a pulse wave and the other end is allowed to move freely.The vibration velocity of the bar free end is measured by a laser vibrometer.The dynamic parameters are calculated from the vibration velocity ratio between the long bar and the short bar over a wide frequency range since the driven signal of the pulse wave is a broadband signal.The frequency range of the measurements can be further expanded through data fitting.The results agree well with that of commercial viscoelastic instrument.