Acoustic emission source location in composite structure by Voronoi construction using geodesic curve evolution

Abstract

Conventional analytical/numerical methods employing triangulation technique are suitable for locating acoustic emission (AE) source in a planar structure without structural discontinuities. But these methods cannot be extended to structures with complicated geometry, and, also, the problem gets compounded if the material of the structure is anisotropic warranting complex analytical velocity models. A geodesic approach using Voronoi construction is proposed in this work to locate the AE source in a composite structure. The approach is based on the fact that the wave takes minimum energy path to travel from the source to any other point in the connected domain. The geodesics are computed on the meshed surface of the structure using graph theory based on Dijkstra's algorithm. By propagating the waves in reverse virtually from these sensors along the geodesic path and by locating the first intersection point of these waves, one can get the AE source location. In this work, the geodesic approach is shown more suitable for a practicable source location solution in a composite structure with arbitrary surface containing finite discontinuities. Experiments have been conducted on composite plate specimens of simple and complex geometry to validate this method.

Structural Health Monitoring of Wind Turbine Blades: Acoustic Source Localization Using Wireless Sensor Networks

“…To trace the active region within a large structure of wind turbine blade (i.e., in twodimensional position), AE wireless units can be spaced apart on the blade and AE sources can be assumed to be within a region and less than halfway between the wireless units. In this case, methods explained in [21] can be applied to trace the AE source. In this paper, the zonal localization is used to specify the active blade, and the results of this localization are presented in Section 5.…”

Detecting and locating damage initiation and progression in full-scale sandwich composite fuselage panels using acoustic emission

“…The incorporation of direction-dependent velocity in source location calculations for composites has been demonstrated by Gangadharan et al 20 and Kundu et al 21 Ciampa and Mia 22 further improved the localization method of manually simulated AE sources in composites of unknown lay-up and thickness. The method identifies the time of arrival of the first flexural Lamb mode and the source location is identified with a back-tracking approach using redundant measurements.…”

Strategies for Extracting Damage Induced AE Signals from Different Type Noise-Like Backgrounds for Carbon-Fibre Reinforced Polymers

“…Spatial selection requires localization of acoustic emission sources with an acceptable error, which in the case of composite materials has proven to be a rather complex problem [14][15][16][17]. Parametric selection is effective when the maximum amplitude of the acoustic emission pulses is, on average, at least 5 dB higher than the amplitude of the noise component.…”