Traveling wave characteristics on two-dimensional finite structures using Hilbert transform

In this study, we develop a method to analyze traveling waves generated by two bending modes of a two-dimensional piezoelectric actuator. This actuator has a composite structure constructed by a stainless-steel plate and piezoelectric PZT sheets. A developed analytical model analyzed the characteristics and efficiency of the traveling waves generated by the superposition of different bending modes. Using the multi-integer frequency, two-mode (MIF-TM) driving method, a steady traveling wave can be generated using two driving frequencies with an integer multiple relationships and near two bending modes. The optimization of the driving parameters is conducted by developing a cost function using the Hilbert transform, in which the driving voltages and the phase difference between the two driving frequencies are used. Finally, this analysis method is verified by using the finite element method.