Background

Harvesting ambient or wasted energy has long been a goal for powering energy‑autonomous electronic devices, among such sources of ambient energy vibration has seen most attention due to its high energy density and widespread occurrence. Various methods have been developed and successfully implemented but are limited due to their linear response and narrow operational bandwidth. Operating such devices in nonlinear off resonance conditions results in a significant reduction in power output. Our magnetic rolling pendulum technology introduces a nonlinear mode of operation in which the energy harvester has a larger power bandwidth in the secondary nonlinear vibrational resonance rather than the primary linear resonance.

Technology Overview

The magnetic rolling pendulum (MRP) is a nonlinear vibration energy harvester, which converts ambient vibrations to electricity. It consists of four permanent magnets and two coils Figure 1, which utilise linear inertial forces from motion of the device combined with nonlinear spring forces generated by the magnets to generate energy by variation in the magnetic flux experienced by the coils through Faraday’s law. Lab based prototypes have been constructed operating in the frequency range 13.2 ‑ 18 Hz and successfully demonstrated an increase in bandwidth and peak power generation where the contribution from the secondary resonance is nearly twice that of the primary resonance. The frequency range over which the devices operate can be manipulated to suit different vibration sources and environments.

Further details are available in recent publications: https://doi.org/10.1063/1.5097552 and https://doi.org/10.1016/j.apenergy.2019.113822

Benefits

The key benefits of the technology are:

Increased power output
Operation over a wider range of excitation frequencies

Applications

Potential applications for the technology include:

Machine condition monitoring
Large scale asset monitoring (e.g. water systems, utilities, oil & gas production equipment)
Wearable devices
Distributed sensor networks
Infrastructure monitoring (e.g. bridges & tunnels)

Opportunity

The University is seeking potential partnerships with a view to developing research collaborations or commercial licensing opportunities.

Nonlinear Energy Harvesting Device

Patents

IP Status

Seeking