Design and study of an eccentric wheel drive-based rotating piezoelectric energy harvester

A nonlinear rotating piezoelectric energy harvester (N-RPEH) driven by eccentric wheels is proposed to collect rotational energy in the environment. Driven by external rotational motion, an eccentric wheel converts rotational motion into linear motion and realizes electrical energy output through magnetic coupling. To increase the effectiveness of the equipment's energy conversion process, this article aims to transform the rotational motion of an eccentric wheel into a linear motion of a motion board. The effects of the motion board's length L, the cylindrical magnet's height H, and the mass block M at the piezoelectric patch's end on the output performance of N-RPEH are explained by theoretical modeling and simulation. Through theoretical analysis, simulation, and experiment, it is found that when L = 120 mm, H = 6 mm, and M = 5.0 g (medium mass), the output voltage reaches the maximum of 14.16 V. Under this parameter, N-RPEH can produce a maximum power of 7.0688 mW when the external resistance value is 2 kΩ. Application experiments show that N-RPEH can light up 60 light-emitting diodes. Therefore, the proposed N-RPEH can effectively collect rotational energy and has a wide range of potential applications in wireless sensor networks.