A Novel Mechanical Energy Harvesting Device with Steady Output Based on Pendulum-Mainspring-Dynamotor Transmission Mechanism

Abstract

In this paper, a novel mechanical energy harvesting device with relatively steady output is proposed which consists of a pendulum, a mainspring, a dynamotor and two gear sets (PMD-MEH). Through the deceleration gear set, the mainspring temporarily stores the energy from the irregular vibration of the pendulum. The acceleration gear set facilitates the gradual release of the stored energy from the mainspring, ultimately driving the dynamotor to provide a continuous and relatively steady output. Experiment results indicate that the PMD-MEH achieves a peak open-circuit voltage of 5.8V and a peak short-circuit current of 85.8mA when the mainspring is fully wound. Additionally, by simulating external mechanical vibrations using an industrial robot, the PMD-MEH yields an average open-circuit voltage of 2.1V and a short-circuit current of 33.15mA, with an average output power density of 5.7W/m2 when the vibration amplitude is 500 mm and the robot arm motion velocity is 1.6 m/s. Given that the PMD-MEH's structural design meets both innovative and practical requirements, coupled with its high efficiency in energy harvesting and conversion, it holds significant potential in widespread applications such as powering electronic devices and intelligent monitoring systems in the future.

Keywords: Mechanical energy harvesting, Mainspring, Pendulum, Dynamotor, Steady output