Chinese researchers design smart energy harvester on human knee

WASHINGTON. KAZINFORM - Chinese researchers have developed a device that can harvest energy from its wearer's knee and generate 1.6 microwatts of power while the wearer walks at a normal speed without any increase in effort, Xinhua reports.

The study published in the latest edition of Applied Physics Lettersdescribed the device that can power gadgets like health monitoring equipmentand GPS devices.

A group of researchers from the Chinese University of Hong Kong (CUHK)used a smart macro-fiber material, generating energy from any sort of bendingto create a mechanism similar to the slider-crank used to drive a motor.

They attached the device to the knee since the knee joint has largerrange of motion than most other human joints. Every time the knee flexes, thedevice bends and captures the biomechanical energy through the natural motionof the human knee, according to the study.

The prototype device weighs only 307 grams and was tested on humansubjects walking at speeds from two to 6.5 kilometers per hour. It can be usedby climbers and mountaineers.

The wearers' breathing patterns with and without the device indicatedthat the energy required to walk was unchanged, meaning that the device isgenerating power at no cost to the human.

«Self-powered equipment can enable users to get rid of theinconvenient daily charge,» said Liao Wei-Hsin, professor of engineeringat CUHK and the paper's corresponding author.

This energy harvester would promote the development of self-poweredsmart wearable devices, according to Liao.