Enhanced Nondestructive Evaluation via Model-assisted Ultrasonic Imaging

ABSTRACT: The proposed research program will develop tools for the improved characterization of defects in complex aircraft structures. The resulting Structural Damage Sensing (SDS) tools are expected to provide at least a 20% improvement in detection capabilities. This will be achieved through the application of transducer arrays for generating, sensing and processing of ultrasonic bulk and guided waves. Phased arrays and distributed arrays will be considered along with adaptive imaging schemes updated by results from efficient numerical models also developed as part of the research. The study will rely on results and procedures which have been proven effective for the analysis of low-frequency ultrasonic waves and guided wave based imaging. These procedures will be extended to bulk waves for high-frequency, high resolution imaging. BENEFIT: Structural Damage Sensing (SDS) systems which will be developed during this work are important for safety, efficiency of maintenance, platform availability and longevity. Safety is related with the SDS potential to detect and assess hazardous rogue flaws before they become critical to the aircraft. Efficiency of maintenance is associated with the Department's of Defence (DoD) major objective to migrate to condition-based maintenance by improving maintenance agility and responsiveness for quicker turnaround times, increased operational availability, and reduced total life cycle ownership cost. The customizable SDS tool as envisioned in this effort could be used in many industries such as aerospace, automotive or machinery to significantly improve the reliability of various systems. Through the innovative theoretical developments and practical demonstration of these innovations, the Structural Health Monitoring/Nondestructive Evaluation/Prognosis and health management (SHM/NDE/PHM) technology under development here, offers a tremendous opportunity for accurate and rapid damage assessment.