Abstract
Membrane structures are intensively paid attention as large deployable and light-weight structures. Membranes are vulnerable to wrinkles resulting in the degradation of structural performance. We suggest a new wrinkle detection method using elastic wave propagation on the membranes as an alternative and supplementary way of optical methods using cameras. In this paper, elastic wave propagation behavior in the wrinkled membrane is analytically investigated by simplifying a wrinkle as the combination of thin plane plates and circular plates. Effects of the frequency of elastic waves and the curvature of wrinkle on the reflection/transmission of the waves at the wrinkle are investigated. The wave transmittance across the wrinkle is calculated and discussed to propose a detection method of wrinkles in membranes. Experimental demonstration of wave propagation in wrinkled membrane is performed using piezoelectric actuators and Multi-axis Vibration Evaluating System (MaVES). It is confirmed that elastic waves with frequencies below the circular frequency cannot propagate across the wrinkle, while waves with higher frequencies can transmit through the wrinkle.
