A compact mechanical energy harvester for multi-scenario applications in smart transportation

Harvesting mechanical energy from traffic environments is an effective way to power low-power wireless sensors. In this paper, a compact mechanical energy harvester (MEH) is designed for common traffic scenarios, converting reciprocating vertical vibrations into unidirectional rotational motion of a generator through the use of two one-way clutches integrated within bevel gears. A nonlinear coupling model is established to analyze the MEH during its engagement and disengagement phases. This paper focuses on the dynamic characteristics under different load conditions and the safety implications of integrating the MEH into railway operations. Laboratory tests are conducted to evaluate the effects of different harmonic excitations on input force, angular velocity, and output voltage, validating the dynamics model and assessing its performance. Experimental results demonstrate that the MEH can achieve an average power of 42.73 W and a peak power of 96.05 W under harmonic excitation. In simulated scenarios, the peak powers that can be obtained in the freight railway scenario and road sidewalk scenario are 44.3 W and 4.92 W, respectively. These findings demonstrate the significant potential of the proposed MEH for powering electronic devices in traffic settings.