Hybrid Acoustic Emission and Guided Wave Inspection System for Radar Tower Structures

A novel hybrid acoustic emission (AE) and guided wave (GW) inspection approach for radar towers inspection is presented. Keeping aging radar sites (many are over 50 years old) in good repair is important because they are critical intelligence components that provide advanced aircraft notification. This proposed work will continue development of new, patent-pending shear-type AE sensors, and apply methods to supplement passive AE inspection with active GW inspection on radar towers. In Phase I, the use of new, dual AE-GW shear-type sensors has shown improved performance over conventional AE sensors in several areas, including source localization accuracy and decreased sensitivity to environmental noise. Lower noise levels are important because times of high environmental noise (e.g., storms) often correspond to times of damage progression due to large external forces. Additionally, the sensors use the shear wave velocity for location calculations, simplifying the process and removing a source of user error. A hybrid AE-GW inspection technology has the potential to revolutionize the traditional AE market, allowing inspection redundancy and significantly improved damage classification. Phase II efforts will make great strides towards the commercialization of this technology with continued development of new shear sensors and demonstration of successful remote radar tower inspection.