Robust self-sensing Smart Fastener system interfaced with onboard HUMS Navy SBIR FY2016.1 Sol No.: Navy SBIR FY2016.1 Topic No.: N161-009 Topic Title: Robust self-sensing Smart Fastener system interfaced with onboard HUMS Proposal No.: N161-009-0429 Firm: Acellent Technologies, Inc. 835 Stewart Drive - Sunnyvale, California 94085 Contact: Howard Chung Phone: (408) 745-1188 Web Site: http://www.acellent.com Abstract: Fatigue cracks originating at fastener thru-hole locations are a primary damage mode in multi-layered joints. If these cracks remain undetected, a joint failure can follow with potentially catastrophic consequences. In-hole inspection of joints is difficult, costly, and time consuming. A sensor integrated with a fastener capable of detecting cracks in the borehole surface - i.e. a Smart Fastener - would significantly reduce the maintenance burden for aircraft operators. A Smart Fastener is far superior to manual inspection methods for layered joints as it is capable of continuously monitoring a borehole, without disassembly of the structure. The goal of the current program is to fully develop a Smart Fastener for damage detection in multi-layer aircraft structures. Previous work done in this area will be used as a basis for the development. The program will demonstrate the robustness of the enhanced Smart fastener in relevant operational environments and its capability for usage in actual aircraft structures while interfaced with the aircraft onboard HUMS system. The work will be done in close collaboration with Sikorsky Aircraft who is supporting the development. Phase I will demonstrate feasibility of the Smart Fastener in crack initiation detection. Complete fastener development will be done in Phase II. Benefits: The overall goal of the proposed Phase I and Phase II effort is to develop and implement a self-sensing Smart Fastener monitoring system for detection, localization and quantification of damage severity in fastener holes in multi-layer airframe structures. The goal will be to turn this concept into a commercially viable product that will be available for widespread trial and adaptation upon project completion. The proposed development can be potentially used in a number of applications and is not limited to the aircraft industry. In the future, this system can be applied to heavy machinery industries where critical components are joined by fasteners, etc. The development of these sensors will also have broad commercial applications for structural health monitoring of mechanical joints on commercial aircraft, ships, and civil structures such as bridges. It is expected that once developed, the system will provide the following advantages:  Low-cost of monitoring  One-of-a-kind plug-and-play system for accurate damage detection, localization, and quantification in fastener holes  Only system available in the market that is applicable for monitoring of inaccessible areas on structures without structural disassembly  Fast, reliable and accurate damage diagnostics and characterization  Minimizes the amount of inspection required  The flexible thin film technology enables easy conforming of the sensor network to any fastener.  Extremely portable and sustainable sensor network technology Return