Hydraulic-Based Rotary Electromagnetic Energy Harvester for Road Speed Bumps

Vehicles dissipate kinetic and potential energy over speed bumps. This wasted energy has immense potential for powering wireless sensor networks and intelligent transportation terminals. A hydraulic-based rotary electromagnetic energy harvester for road speed bump is proposed to recycle this mechanical energy. The vertical force from the vehicle passing over a speed bump is converted into horizontal motion through the transmission mechanism. And the fluid within the hydraulic cylinder is driven by the transmission mechanism to flow cyclically in the pipeline. Impeller of the electromagnetic generator is rotated by the high-speed flow of fluid, thereby generating electrical energy that can be stored in super capacity. Compact design is adapted to effectively utilize the internal spatial characteristics of the speed bump and minimizes damage to the road surface. An experimental testing was introduced using motor-controlled equipment to investigate the effects of different loading speeds and device pipe diameters on the output energy of the energy harvester. The optimum load for the harvester was determined to be 280 ohms at a rocker loading speed of 21 r/min, resulting in an output power of 0.35W.