Anomaly Detection in Curved Composites

The detection and characterization of strength-reducing features in composite structures such as rotor blades, notably in the H-53 Heavy Lift Helicopter program, is of critical importance to the Navy. Nondestructive inspection of bridging in tight bends of composites in thick sheets of laminates is one area where there is a lack of capability at the right cost. Intelligent Optical Systems (IOS) proposes Anomaly Detection in Curved Composites (ADeCC), based on detecting guided wave ultrasound for detecting and quantifying bridging over relatively large areas to significantly improve quality control of thick composite parts subject to such defects. An affordable, nondestructive tool is proposed using flexible optical fiber transducers for ultrasound collection that will reliably detect bridging in tight radii. The graphite/epoxy and fiberglass/epoxy laminates of geometries and up to 0.75 in. thick will be obtained from the National Composite Center in Kettering, OH for testing in Phase I. The goal is to detect bridging and other materials or obstructions between layers in samples of molded-in metal sections. After demonstration of feasibility, Phase II will focus on delivering a complete single-command operated hardware and software system that includes data analysis, with detection of bridging and a corresponding confidence level metric.