A Wireless Demodulation Method for Acoustic Emission Sensing

Abstract

As an effective non-destructive testing method, acoustic emission detection technology has been widely used in structural health monitoring (SHM). This paper proposes a wireless monitoring system based on acoustic emission technology. Specifically, a wireless communication system based on amplitude demodulation of acoustic emission signals is designed. Envelope detection is adopted at the receiving end to retrieve the original acoustic emission signal via onboard technology. Compared with the conventional coherent demodulation method, the propose approach avoids the need of coherent carrier at the receiver node, which reduces the complexity of the detection system. The successful sensing, transmission and recovering of a simulated acoustic emission signal using the Lamb wave was demonstrated. The proposed wireless acoustic sensing technique is further used for the acoustic emission signal monitoring of three tensile test specimens with different initial configuration. The approach could clearly distinguish the different stages of the specimen during the tensile test, suggesting the great potential of this approach for the structural health monitoring applications.