An autonomous structural health monitoring system (SHMS), composed of a network of sensors with embedded microprocessors, can offer economically viable life-cycle benefits due to the potential for greatly increasing air safety, improving operational capability, reducing maintenance downtime, and enhancing component reliability of in-service airframe structural systems. The resulting system is expected to become pervasive during the next decade. However, a hardware/software framework that will allow this technology to be employed for health monitoring is yet to be established.
The development of health monitoring framework based on smart sensors will require a major paradigm shift involving sensor hardware/system software, smart materials, on-board SHM algorithms, and wireless communication. The true autonomy of wireless sensors depends on their reliable operations for extended times without human intervention. This proposal seeks to develop self-contained wireless sensors for interrogating the damage in monitoring high-stress and flight-critical areas of aerospace structures. The wireless sensors can be readily mounted on the structure in a noninvasive manner, in particular in the areas of limited accessibility. A modular hardware prototype (MHP) developed at NC State University (NCSU) will be employed as a framework of this research. Special attention will be given to developing a miniature Wireless Intelligent Sensor (WIS) for sensing allowing continual monitoring of aerospace structures and real-time damage localization. These low-cost self-powered sensors with self-diagnosis and self-calibration capabilities will allow damage detection at the local network in real time. The ultimate goal of this investigation is to provide flight crews or ground control center with a versatile and powerful tool to visualize the damage in chronic structural areas. The proposed work builds on a highly successful project by the PI. The research plan consists of three major tasks. Namely: . Develop, and build an MsM energy harvesting subsystem; . Develop self-diagnosis and self-calibration capabilities in WIS; . Prototype and test the WIS in both laboratory and field environments.
The proposed research will lay the groundwork for a novel autonomous wireless smart sensor network technology for intelligent monitoring of complex aerospace systems and a broad set of physical phenomena. It is envisioned that the proposed work will significantly advance scientific and engineering knowledge in the areas of wireless sensor technology, digital signal processing, innovative on-board SHM algorithms, energy harvesting, and power management.
