A Seesaw-Structured Energy Harvester With Superwide Bandwidth for TPMS Application

In this paper, we introduce a novel seesaw-structured energy harvester for tire-pressure monitoring system (TPMS) applications. The unique design of the proposed energy harvester can effectively avoid the influence of enormous centrifugal force, which is attributed to the balance characteristic of seesaw structure. Two magnets placed on the seesaw end could swing the seesaw structure in every rotating cycle with the help of external noncontact magnetic repulsive force, and subsequently this unbalanced seesaw structure impacts the polyvinylidene difluoride (PVDF) cantilevers to generate the power. A miniature energy harvester prototype is fabricated using a 3-D printing technique. In the performance testing experiment, a peak voltage of 4.6 V and a constant peak output power of 36 μW with the optimized load resistance value of 0.6 MΩ are achieved within a superwide rotating frequency range of 215-965 r/min (25.7-115.4 km/h for a real car). Moreover, an average power per second is 5.625 μW at 750 r/min, which could be potential power supply for the TPMS application.