Feasibility study of impact-based piezoelectric road energy harvester for wireless sensor networks in smart highways

- Impact-based harvesters convert input energy to electrical power efficiently.
- Harvester buried underneath road; axial load from moving vehicles used as input.
- Performance verified through ideal case and real-road simulations.
- Can be used as power sources for wireless sensor networks in smart highways.

The purpose of this study is designing and examining impact-based piezoelectric road energy harvesters as power sources of a variety of sensors and smart highways. The impact-based piezoelectric road energy harvesters (15 × 15 × 9 cm3) developed in this research can convert the input energy efficiently into electrical power. The output power of the proposed harvester is significantly higher than that of the existing harvesters. Moreover, in previous studies, simple experiments were performed for measuring the output power of a road energy harvester, with no consideration for the practical road conditions. In this study, the output power is measured using machines that can simulate the practical road conditions. First, the output power of the harvester is measured using a universal testing machine (UTM) that can apply an axial load with a controlled loading frequency. Then, a third-scale mobile loading simulator (MMLS3) that can simulate practical traffic load on a lab scale is used. As a result, the maximum output power of the road energy harvester is 483 mW(21.47 W/m2).