Traditional mechanical watches can be grouped into 2 types, manual and automatic. The automatic watch is powered by a spring which winds when the arm is moved, it stores energy and is used to power the watch even when it is not being worn. However, due to the structural constraint, the mechanical friction is high which can lead to mechanical failure.
To address this issue, Prof. Liao Wei-Hsin, Chairman of the Department of Mechanical and Automation Engineering, has developed an embedded energy harvester which is very efficient in generating electricity to sustainably power the smart watches and wristbands.
CUHK Faculty of Engineering Develops Effective Energy Harvester Breaking through the Limitation of Battery Life of Smart Watches and Wristbands Earning International Recognition: https://www.cpr.cuhk.edu.hk/en/press_detail.php?id=3396&t=