PITA Fiscal Year 2008 Projects - Innovative Infrastructure System
   Assessment Technology

Acoustic Emission Sensors using Novel MEMS Design

Principal Investigators: Irving J. Oppenheim, David W. Greve

Acoustic emission testing is used commercially to inspect fatigue cracks in civil infrastructure components such as steel bridges, pipelines, and pressure vessels. In previous work, researchers at Carnegie Mellon and Lehigh have developed and demonstrated MEMS sensors to detect acoustic emissions. The investigators at Carnegie Mellon have worked with an industry participant, WavesInSolids, to incorporate the MEMS devices in a “Wireless Remote Structure Integrity Monitoring System.” In this project, the investigators at Carnegie Mellon will deliver to WavesInSolids new versions of the MEMS sensor system that are improved in sensitivity and compactness, will interface the MEMS system with local signal processing, and will test the integrated system in the field on railroad bridges. The investigators will improve device sensitivity by designing and fabricating a new device that takes advantage of a novel MEMS design feature that was recently demonstrated. The new device will contain other novel sensors, also recently demonstrated, that respond to acoustic emission motions in all three principal directions, rather than the unidirectional response of commercial sensors.