Damage Detection With Single Receiver by Multidirectional Dispersive Phononic Crystals.

Lamb wave receiver arrays are commonly utilized in nondestructive testing (NDT) and structural health monitoring (SHM) systems to enhance the identification and localization accuracy of structural damage. However, excessive deployment of Lamb wave receivers inevitably increases the hardware cost and additional complexity of the testing system. Here by introducing 3-D-printed acrylic phononic crystals (PCs) with single receiver, we aim to overcome the existent systematic limitation by customizing propagation characteristics of Lamb waves based on local resonance effect. A sensing device related to multidirectional periodic structure is proposed to introduce unique amplitude-frequency modulation to identify the orientation of scattering Lamb wave induced by damage. Velocity dispersion is extracted from time-frequency spectra of scattering signals to estimate the damage distance and position. Our proposed single multidirectional receiver, has experimentally demonstrated the effectiveness of damage localization with minimal error and significant stability whether it is deviated or not, which paves the avenue for the potential development and application of ultrasonic damage detection in NDT field.