Good vibrations from MEMS based energy harvester
1 min read
A team from the University of Cambridge's Centre for Smart Infrastructure and Construction has developed a mechanical amplifier that can convert ambient vibrations into electricity more effectively.
The device is thought to have applications in condition monitoring of roads, bridges and tunnels, as well as powering wearable medical devices and extending the life of batteries in mobile phones.
While self powered batteryless devices are not new , they have two key technical limitations: low output power density; and the mismatch between the narrow operational frequency bandwidth of conventional energy harvesters and the wideband nature of vibrations experienced by bridges, tunnels and roads.
CSIC has addressed these issues by basing its harvester on a phenomenon known as parametric resonance. The energy harvesting device, consisting of a micro-cantilever structure and a transducer, can be created using MEMS technology. When force is applied to the cantilever perpendicular to the length instead of transversely, parametric resonance can be achieved, generating more energy from the same amount of vibration.
Prototypes of MEMS and macroscale devices based on these principles are said to have demonstrated a significantly improved power output and a wider operational bandwidth relative to current devices.