On the Joint Optimization of Energy Harvesting and Sensing of Piezoelectric Energy Harvesters: Case Study of a Cable-Stayed Bridge

There is growing evidence that piezoelectric energy harvesters (PEHs) not only generate electricity from vibration sources, but their voltage signals can also be utilized simultaneously to sense various contexts of interest. Little is known, however, about any potential trade-off between its energy harvesting and sensing performances within the design space of the PEH device. Lack of such knowledge prevents optimal design of dual-functional PEH devices that are expected to be used both as a power source and a sensing system. In this paper, using an extensive vibration dataset collected from a real-world cable-stayed bridge, we investigate the simultaneous energy harvesting and vehicle speed sensing performance of PEH devices with varying geometrical shapes. Our results reveal that both energy harvesting efficiency and sensing accuracy depend significantly on the shape of the PEH, and there exist configurations with more favourable harvesting and sensing performances. This finding is expected to open up new opportunities for jointly optimizing energy harvesting and sensing for various types of PEH devices and applications.