Cylinder‐based hybrid rotary nanogenerator for harvesting rotational energy from axles and self‐powered tire pressure monitoring

Abstract Tire pressure monitoring plays a pivotal role in vehicle safety system. However, as a conventional battery‐operated electronic system, regularly replacing battery remains a great inconvenience in wide‐distributed tire pressure sensing. Here, we introduce a self‐powered tire pressure monitor by using a rotary cylinder‐based hybrid nanogenerator as a sustainable power source. The designed energy harvester, by hybridizing a triboelectric nanogenerator (TENG) and electromagnetic generator (EMG), can scavenge rotational energy from rolling axles. Integrating with transformers, the hybrid nanogenerator can achieve an open‐circuit voltage of 16 V and short‐circuit current of 0.1 mA at the rotation rate of 150 rpm, respectively, with the maximal output power of about 1.8 mW at the loading of 20 kΩ. Via a programmable software, the hybrid device can operate as a self‐powered counter and timer for potential speed detecting. Further, it has been demonstrated that the hybrid nanogenerator is capable of triggering a transmitter‐integrated tire pressure sensor for self‐powered monitoring tire pressure in real time. This study expands applications based on TENGs in automobile engineering, which might promote the development of intelligent driving and traffic safety engineering.