Due to the wave propagation characteristics of the beam, it is difficult to reduce the vibration in the beam by using the destructive interference of the waves. At the free end of the cantilever, the wave generated by the external excitation is propagated to the fixed end with the transverse vibration characteristics of the cantilever as a transfer function. If this transfer function can be derived, the output signal can be predicted from the input signal, and the waveform for vibration reduction can be calculated. In order to generate the calculated waveform, the external excitation source should be placed, and the transfer function between the input signal and the output signal of the source is calculated using the same method to derive the dynamic characteristics of the longitudinal axis. These wave propagation characteristics are essential to reduce the vibration of the beam.