Design and experimental study of a piezoelectric energy harvester in automotive spokes

Abstract

In order to supply power for the wireless sensors in wheels, a piezoelectric energy harvester installed in spokes is proposed in this paper. The piezoelectric cantilever beam is fixed in the spoke, which has higher practicability than the method mentioned in the related research. The periodic excitation is generated by the gravity effect of the free-end mass in the rotation, and the safety limiting structure is designed. A dynamic model was derived through the Euler–Lagrange method and verified by experiments. Based on the numerical simulation of the model, the parameter design of the harvester was carried out in detail for the R16 size rim. In order to verify the performance, an experimental platform was built with piezoelectric composite fiber materials. The influence of the limiters on the steady state and the sweep response was studied, and the energy harvesting effect was further tested by the experiment on the road. The results show that the harvester designed can obtain 82–1003 μW energy at 50–70 km h−1, which provides the possibility of establishing a self-sufficient intelligent wheel system without maintenance.