Motion is involved in our everyday life - walking, running, swinging arms… … It would be convenient if these movements can be converted into useful energy. There are other methods of energy generation such as piezoelectricity - produced through deformation, and triboelectricity - energy generation through contact-separation process of two different materials. “Renewable energy generation of portable and wearable devices” is an energy related engineering project that aims to find an efficient solution of converting motion energy into electric energy through consistent, portable sources. The source’s oscillation motion requires large amplitudes in order to increase the efficiency of energy generation. Locations on human’s body such as wrists or ankles are ideal sources of energy harvesting. Energy collection is done through the use of a pendulum that runs gear systems and generators in portable devices such as watches. The models are 3D designed and constructed to test their mechanism. Two models utilizing a brushed DC motor incorporate a single-bearing system and a ratchet gear system, used for single-direction conversion. The model utilizing a brushless motor doesn’t require direction convertors, which only consist of gear systems that increase the rotational ratio. The electric potential of the three models are tested and conclusions are drawn on their efficiencies and consistency, which will be the basis of future works aiming to minize the models and apply them into portable devices.

Xinkai Guo. Renewable Energy Generation of Portable and Wearable Devices. International Journal of Frontiers in Engineering Technology (2024), Vol. 6, Issue 4: 59-65. https://doi.org/10.25236/IJFET.2024.060410.

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