Linkage-based electromagnetic energy harvester for road infrastructure

Abstract This paper introduces the design, fabrication, and dynamic modeling of a new linkage-based electromagnetic energy harvester for roadways. The system addresses key challenges often overlooked, including ensuring driver comfort, easy installation under a speed bump, low complexity, high power density, and high durability. It features a transmission module and an energy generation module. The transmission module utilizes mechanical linkages to amplify the input displacement by a factor of nine before transmitting motion to the generator. The energy generation module includes a pair of gearboxes, two generators, and energy storage circuits. The innovative system is optimized within operational space; its linkage-based transmission offers a simpler design, reduced transmission losses, durability, and quick response to vehicle loads. Additionally, the maximum vertical deflection is limited to 3 mm to consider driver comfort. Experiments were conducted at 0.5 Hz, 1 Hz, and 1.6 Hz. Experimental and simulation results closely align, except at low frequency (0.5 Hz). An average output power of 0.56 W and energy output of 0.35 J per cycle are achieved at 30% efficiency, with an input frequency of 1.6 Hz and an amplitude of 3 mm. Field tests show the maximum power ranges from 2.75 W to 4.5 W at lower vehicle speeds. The system’s power density reaches approximately 67 W m −3 at a displacement amplitude of 3 mm, which is a high value compared to other reports in the literature.