Buffering and Self-Recovery-Enabled Road Vibration Energy Harvester for Smart City Applications

The advancement of smart transportation depends on the integration of multiple Micro-Electromechanical Systems (MEMS), with the challenge of ensuring their continuous and reliable power supply remaining urgent. This paper presents a bidirectional compression energy harvester with buffering and self-recovery functions, which utilizes road vibration excitation for power generation. By employing a spring and bevel gear mechanism integrated with a one-way bearing, the harvester converts external irregular excitation into continuous unidirectional rotation of the rotor, subsequently converting rotational kinetic energy into electrical energy via electromagnetic induction. The dynamic and power generation models of the harvester are developed and validated through prototype testing. With the use of a highly efficient energy harvesting circuit designed for coil power generation, the harvester successfully charges capacitors of 0.5, 1, 2, and 4 F to 5 V within time intervals of 15, 26, 71, and 149 s, respectively, under excitation conditions of 1 s period, 30 mm amplitude, and MVIII magnet arrangement. Under a single excitation from an adult, the harvester achieves an average output power of approximately 3.92 W and generates 13.51 J of electrical energy. These results demonstrate the harvester’s excellent energy harvesting performance. Its potential for powering MEMS is indicated, providing a promising solution for continuous, real-time monitoring in smart transportation systems.