Michigan researchers have revealed a major breakthrough in harvesting energy from human motion.密歇根的研究人员取得了一项重大突破， 可从人体动作中收集能量。They say it could lead to smartphones powered for a week by the motion of a swipe being harvested.Michigan State University39;s low-cost device， known as a nanogenerator， has already been tested. operated an LCD touch screen， a bank of 20 LED lights and a flexible keyboard， all with a simple touching1 or pressing motion and without the aid of a battery.The groundbreaking findings， published in the journal Nano Energy， suggest 39;we39;re on the path toward wearable devices powered by human motion，39; said Nelson Sepulveda， engineering and lead investigator2 of the project.39;What I foresee， relatively3 soon， is the capability4 of not having to charge your cell phone for an entire week， for example， that energy will be produced by your movement，' said Sepulveda， whose research is funded by the National Science Foundation.The process starts with a silicone wafer， which is then fabricated with several layers， or thin sheets， of environmentally friendly substances including silver， polyimide and polypropylene ferroelectret.Ions are added so that each layer in the device contains charged particles. by human motion， or mechanical energy. ferroelectret nanogenerator， or FENG， and is as thin as a sheet of paper. to power the LED lights was palm-sized， for example， to power the touch screen was as small as a finger.Advantages such as being lightweight， flexible，， scalable， low-cost and 5 could make FENG 'a promising6 and alternative method in the field of mechanical-energy harvesting' for many 7 electronics such as wireless8 headsets， cell phones and other touch-screen devices， the study says.