Description: To address NASA's need for advanced nondestructive evaluation (NDE) of complex built-up spacecraft structures, Physical Optics Corporation (POC) proposes to develop a new Multifunctional Compton Inspection Tool (MCIT) for operation onboard the International Space Station (ISS), based on POC's previously developed Compton imaging tomography (CIT) approach. CIT works by acquiring two-dimensional (2D) images of Compton-scattered X-ray radiation produced by multiple slice views of the object, with subsequent three-dimensional (3D) reconstruction of the inspected structure for high-resolution detection and localization of defects. The MCIT incorporates new features and modifications of the CIT, which permit it to operate in multiple modes with enhanced functionality, smaller form factor, and smaller weight. The proposed MCIT will allow noncontact, single-sided inspection of various spacecraft structures (such as micrometeoroid and orbital debris (MMOD) shields, pressure vessels, ISS modules, and thermal protection of visiting spacecraft) from either within the pressurized habitable compartments or open space. In Phase I POC will demonstrate the feasibility of using MCIT for NDE of spacecraft components by fabricating and testing a TRL-4 prototype, with the goal of achieving TRL-6 by the end of Phase II.

Benefits: The primary NASA application of the proposed MCIT system is a compact NDE system that can be used for in situ nondestructive evaluation (NDE) of the integrity of spacecraft components and structures onboard the International Space Station (ISS), with the capability to provide reliable, high-resolution assessment of the location and extent of damage within micrometeoroid and orbital debris (MMOD) shields, pressure vessels, ISS modules, and thermal protection of a visiting spacecraft. Additional NASA applications include NDE of lightweight spacecraft materials used in the development of advanced aircraft and spacecraft, such as porous ceramics, carbon-carbon composites, metal honeycomb layers, fiberglass, Kevlar®, and aluminum alloys, providing accurate identification, localization, and measurements of all types of internal and surface defects.

Military applications of the MCIT system will include in situ NDE/NDT of large-area nonuniform multilayer aluminum/titanium/composite structures with complicated geometry in military aircraft. The MCIT system will also be used for NDI of airplane, helicopter, and missile parts containing electronics, mechanical components, propellants, explosives, etc., to detect defects and validate integrity. The MCIT system can be incorporated by the U.S. Navy, Army, and Air Force as a reliable, rapid, robotic, easy-to-use NDE/NDT system. Potential DHS applications include the detection of vehicle-borne contraband, drugs, and explosives. The commercial applications of the MCIT system include its use for in situ NDE of large-area nonuniform multilayer aluminum/ titanium/ composite structures with complicated geometry (and combined textile polymeric, ceramic, and metal matrix composite structures as well) in aging and modern commercial aircraft, spacecraft, light marine vessels, and any application requiring defect detection for multilayer ceramic, composite, metallic, and nonuniform plastic structures.