Compton Scattering Three-dimensional Imaging System for in situ Nondestructive Inspection of Large Honeycomb Sandwich Structures

To address the Air Force need for a reliable method to inspect large aircraft structures, Physical Optics Corporation (POC) is continuing the development of a new automatic, three-dimensional (3D) Compton scattering IMaging system for in situ nondestructive inspection (NDI) of large HOneycomb Sandwich structures (IMHOS), providing accurate detection and identification, and precise 3D localization/measurement of possible disbonds, core and skin defects including corrosion, and fluid intrusions. The IMHOS is based on a POC developed high-contrast Compton imaging tomography technique, optimized for NDI of these structures, and POC-patented X-ray imaging optics. The IMHOS is a low-dose, in-field, noncontact system requiring access to structures for inspection from only one side. In Phase II, POC successfully developed, tested, and demonstrated a fully functional (TRL-6) IMHOS system in a realistic industrial environment. In Phase IIE, POC will develop and test a fully functional (TRL-8) IMHOS system, demonstrating accurate detection, spatial localization, and measurement of cracks, corrosion, disbonds, and different skin and core defects of large metal structures of varied geometric forms; including detection of liquid intrusions; and differentiation of the type of liquid (fresh or salt water, oil, or other organic liquids).