This SBIR research (Phase I & II) is to develop a smart nondestructive testing (NDT) system for improved on-line inspection of composite structures in aircrafts, spacecrafts, and launch vehicles. The system uses a unique flexible surface-mounted transducer array to replace the conventional bulky and time- consuming scanning mechanism for C-scan plot generation. It also draws on advantages from ultrasonic testing, mechanical impedance method, and frequency response (modal analysis) technologies. In Phase I, the new transducer element will be fabricated and tried out on composite specimens with different defects implanted. The transducer parameters will be optimized through experiments. Pattern recognition methodologies will be identified for defect characterization. The expert system for defect detection will be developed for the composite test specimens. Finally, the prototype setup for the NDT system will be tested to demonstrate its sensitivity for flaw detection. A successful research effort will provide NASA with a flexible, smart NDT system that works faster and more accurately than conventional methods. A further development of this AI-based NDT system may lead to its application in automation and robotics, where similar NDT tasks can be carried out in adverse or hostile environments. POTENTIAL COMMERCIAL APPLICATIONS A flexible, smart NDT system with high reliability and low operating cost developed in this effort (Phase I & II) may be used for improved on-line NDT inspection on composite materials of NASA's interest, particularly on the composite parts with irregular surfaces. The equipment will have tremendous potential for commercialization in the rapidly growing market of composite materials worldwide. Further extension of this concept may result in its application on metal and geologic materials.
