A hybrid vibration energy harvester based on flexible connection for train monitoring

Unmanned and intelligent train transportation requires the development of traffic-oriented self-powered vibration-sensing technology. To enhance the applicability, host-friendliness, and self-powered performance of current self-powered vibration-sensing systems in train transportation, this work develops a hybrid vibration energy harvester (HVEH) for train monitoring, introducing a rope-driven connection and an electromagnetic-triboelectric hybrid mechanism. The flexible rope-driven connection with a magnetic connector (anti-damage design) is utilized for train suspension vibration input while avoiding potential damage under excessive and multi-directional vibration. Double magnet disk configuration and flywheel design effectively enhance vibration energy recovery from the enhanced electromagnetic generator. The signal of the triboelectric nanogenerator for efficient vibration-sensing. In the verification, HVEH achieves vibration inputs within the permissible intensity range (adjusting the magnetic connector), achieving average power outputs of 44.5 mW (the double magnet disk configuration with a 94 % magnetic field strength improvement achieves a maximum 245.6 % increase in output power), it confirmed the effective self-powered performance. The application potential was verified based on multi-angle tests and random vibration tests. Meanwhile, HVEH achieves a 99.7 % correct vibration-sensing rate. A demonstration of monitoring of freight train suspension vibration is presented. This work contributes to the further optimization and practical application of self-powered vibration-sensing technology in train transportation.