SBIR Phase I: Kaiser Trigger: A Nano-Watt Powered Technology for Ultra-Low Power Fatigue Crack Detection

The broader impact/commercial potential of this project will be the introduction of a new generation of low-power wireless sensors for detecting Acoustic Emission events and crack formation in structures. According to the Federal Highway Administration (FHWA), the US transportation infrastructure has 605,102 operational bridges, of which 66,561 are structurally deficient. The FHWA report also indicates that more than 93% of deficient bridges are more than 30 years old. Many other infrastructure systems such as energy pipelines also suffer from aging. The unique features of the proposed technique, which utilizes a Kaiser Trigger, are its low-cost and ultra-low energy consumption. Thus, its use in low-power wireless sensors make it an ideal solution to this challenging problem. The anticipated benefits and commercial applications of this project are (1) a low-cost and easy-to-use mechanism for effective monitoring, early detection, and timely repair of structural issues on infrastructure systems such as highway bridges; (2) improved public safety, reduced maintenance costs, and extended service life of critical and high-valued infrastructure systems; and (3) commercial applications in monitoring the structural health and integrity of other structures, including airframes, pipelines, cargo cranes, ships, etc. This Small Business Innovation Research Phase I project addresses distributed structural health monitoring (SHM) of infrastructure systems, particularly highway bridges, airplanes, and pipelines. Because the creation of a crack in a structure is accompanied by the propagation of high frequency acoustic emission (AE) waves, wireless AE sensors can be used to detect such cracks. However, one of the main challenges for AE detection sensors involves the AE amplifier, which typically consumes significantly more energy than the amount available in a wireless device with limited energy. As a result, conventional AE detection methods cannot be used with low-power wireless sensors. This project proposes a novel technique, the Kaiser Trigger, which will consume several orders-of-magnitude less energy than conventional AE detection systems. After fabrication and successful testing, the Kaiser Trigger will be integrated into structural health monitoring sensors. The wireless sensors equipped with the Kaiser Trigger and AE detection capability will be a powerful, yet low-cost solution for monitoring infrastructure systems.