A bistable energy harvester for self-powered sensing in rail transport condition monitoring

A bistable vibration energy harvester for rail transport is proposed and developed to harness low-frequency train vibrations for self-powered condition monitoring. The operational vibration data collected from a train is analyzed to identify the design requirements. A free-sliding magnet is placed in a tube with two fixed magnets and limit springs to provide two stable positions for the movable magnet. This bistable behavior enhances the energy harvesting performance and operational bandwidth. A prototype was fabricated and tested using conditions similar to the real train operational conditions. A broad operation bandwidth (20 - 40 Hz) was obtained due to bi-stability. A peak output power of 1.1 mW was measured at 30 Hz and 6g with a 600 \Omega resistive load.