Design development and testing of traffic induced wind based artificial tree type hybrid energy harvester for wireless sensor nodes

Abstract

With the rapid development of the urban system, the structural health monitoring (SHM) of high-rise buildings, flyovers, and bridges have attracted researchers’ attention. Currently, wireless sensor nodes (WSNs) are used for the SHM, however, WSNs use batteries as power sources which have limited shelf life. To attain the self-sustain long-term operation of WSNs, ambient energy from their surrounding can be harvested for their power requirements. In this research, a traffic induced wind based artificial tree type hybrid energy harvester is designed, developed, and tested. The developed prototype is able to harvest traffic induced wind. The prototype consists of multiple piezoelectric leaves and two electromagnetic energy harvesters (EM-EH) - short beam EM-EH and long beam EM-EH. Each EM-EH is composed of a cantilever beam, a permanent magnet, an airfoil, and a planar coil. Test results reveals that at a maximum windspeed of 10 m/s, the prototype can harvest 1.60 μW from a single piezoelectric leaf, 53 μW from a short beam EM-EH and 50 μW from a long beam EM-EH at optimum load. This artificial tree type hybrid energy harvester will help in the deployment of WSNs and in the beautification of the urban system.