A Creative Vibration Energy Harvesting System to Support a Self-Powered Internet of Thing (IoT) Network in Smart Bridge Monitoring

An important challenge for transportation in the United States is the aging of its bridges, and the need to develop smart and reliable methods that can modernize and enhance the bridge monitoring systems. In smart bridge health monitoring systems, various types of embedded and installed sensors have been used to detect and localize four major types of anomalies including: corrosion, delamination, crack, and voids. Sensors are communicating together and/or to the main unit through wireless network communication systems and wireless sensor network (WSN). These days, energy harvesting system has been introduced as one type of endless energy sources to feed wireless sensor network (WSN). Cantilever-based energy harvesters have become a practical power supply for the WSNs, particularly for sensors installed on bridge superstructure’s components like decks, girders, stayed cables. Internet of Things (IoT) networks benefit smart structural health monitoring systems to intelligently process the data of bridge structures. In the IoT networks, there are always some concerns about the loss of wireless data between the sensor nodes and the gateways which is mostly caused by its low-reliable power supply. Therefore, the key challenge ahead in smart bridge monitoring is mainly to increase the harvesting power output. A sufficient and sustainable supply can not only increase their transmission range, but also decrease implementation costs as well as decision-making time. This paper introduces a novel hybrid mechanism to enrich the efficiency of energy harvesting systems used for a cable-stayed bridge. The proposed mechanism enables energy harvesting system to remarkably harness ambient vibrations of an inclined stay cable, and convert them into electrical energy as a power supply for wireless sensor networks. In this paper, the Sunshine Skyway Bridge in Terra Ceia, Florida, USA is selected as the case study. A computational study was performed to investigate the performance of the proposed harvesting set-up for energy production. In a field measurement, a non-contact remote sensing laser vibrometer was utilized to measure vibration frequencies and amplitudes of the cable. Accordingly, the proposed hybrid energy harvesting system was modeled using the finite element method. The simulation results show that the average generated power of the hybrid mechanism can easily satisfy electric power required for a sensor node of the bridge’s wireless sensor network. The most serious challenge for the proposed energy harvester that opens up the potential of future research is harsh environmental conditions like hurricane and long-term sunlight which shorten the service life of the set-up.