A system that can detect cracks in composite structures by using a laser to measure vibration generated by piezoceramic actuators is being developed in the USA by the University of Missouri-Columbia.

Called the boundary effect evaluation method, the system uses piezoceramic patches that are attached to a structure and produce small vibrations with an electrical voltage. A laser vibrometer detects vibration when it scans the structure at uniformly distributed points and the data is analysed to determine the location and size of cracks.

The system's developers claim its main advantage is that it can be used on an intact aircraft without having to disassemble sections of fuselage.

Meanwhile, Texas-based materials science company TRI/Austin is seeking partners to transition its own piezoceramic-based composites structural integrity monitoring system to a commercial product.

The Large Area Health Monitoring Processor acoustic emission system was developed with funding from the US Army and Navy.

Source: Flight International