Polymeric multilayered planar spring-based hybrid nanogenerator integrated with a self-powered vibration sensor for automotive vehicles IoT applications

The industrial revolution in automobiles has offered large-scale integration of sensors and interconnections to facilitate smooth and safe driving. These interconnections draw significant amounts of electricity from the power backups, hampering the overall energy efficiency. Herein, a polymer-based low-stiffness multiturn planar springassisted hybrid vehicle energy harvesting module (VEHM) equipped with a self-powered triboelectric vibration sensor (SP-TVS) is proposed that allows mechano-electrical conversion and detection of wide-frequency and lowamplitude vehicle induced vibration. The cylindrical design consists of a solenoid coil pair wrapped with fluxconcentrating film (FeSiCr-Ecoflex) and a free-ended Kapton spring holding the magnet (on top) for electromagnetic generator (EMG), while an SP-TVS is realized at the upper end. EMG works effectively in a wide frequency and acceleration range (minimum similar to 0.1 g), delivering peak power of 1 mW at 0.1 g and 30 mW (average power: 7.5 mW) at 1 g acceleration whereas, SP-TVS can monitor vehicle-induced vibration under various road conditions in real-time. Finally, VEHM has been successfully demonstrated as a self-sustainable wireless vehicle indoor environment (such as temperature, humidity, ambient light, UV Index, door state, magnetic field, and induced vibration) monitoring system, thus maximizing the overall battery life and with self-powered vibration sensing functionality for future autonomous vehicles platforms.