Studies have reported that propagating waves can be generated in a finite one-dimensional structure by using two piezoelectric actuators. However it is not easy to generate stable and continuous propagating waves due to the finite boundaries. Driving two piezoelectric actuators at two different locations with sinusoidal signals of 90° phase difference, the propagating waves can be generated on a one-dimensional structure. However, the correlation between the actuators and propagating waves is still not clear. In this paper, we adopt shadow Moiré technique to monitor the full-field out-of-plane deformation response of the generated propagating waves in the one-dimensional (1-D) plate with 180 mm in length. A 200-μm-pitch grating was used in this moiré interferometry setup. The moiré fringe images were captured by a high dynamic camera sequentially. Moiré fringes were analyzed by regions of interested (ROI) capturing technique and Fourier transform to retrieve phase information, which included 1-D plate deformation. After the phase was unwrapped and filtered, the instantaneous surface profile was reconstructed. Our experimental results demonstrated that our system can capture propagating waves generated by using the second (60.025 Hz) and the third (109.500 Hz) resonant modes.
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