Fidget spinners were all the rage in 2017. What if we could harvest the energy used to send them spinning to power small devices or wearables? We may be able to soon, thanks to researchers at Osaka Metropolitan University.
The team invented a “dynamic magnifier-enhanced piezoelectric vibration energy harvester” that amplifies power generated from impulsive vibrations such as walking by approximately 90x. They published their results in Applied Physics Letters.
Energy harvesting converts energy, such as heat and light, into electricity. Vibration energy harvesting transforms kinetic energy from vibration into electricity and is unaffected by weather or climate, making it highly practical.
The microelectromechanical system (MEMS) piezoelectric vibration energy harvester is 2 cm in diameter with a U-shaped metal component called a dynamic magnifier. To date, the team succeeded in generating microwatt-level electricity from mechanical vibrations with a constant frequency, such as those caused by motors and washing machines. The team developed and incorporated the U-shaped vibration amplification component under the harvester, improving power generation without increasing device size. They expect the technology to generate electric power from non-steady vibrations as well, including the motion we create when walking, to power small wearable devices such as smartphones and wireless earphones.