Self-powered impact sensor based on electrospun Acrylonitrile butadiene styrene triboelectric nanogenerator for wearable helmet application

Abstract

The recent developments in the self-powered sensing technologies have immensely contributed to wearable energy harvesting systems for safety applications. This study highlights the design, fabrication and evaluation of an intelligent wearable helmet for impact detection by integrating a triboelectric nanogenerator (TENG) based on electrospun Acrylonitrile Butadiene Styrene (ABS). The neat ABS nanofibers produced after the 4 h electrospinning process demonstrated the highest triboelectric output when compared to the 2h, 6h, and 8h electrospun samples with an open circuit voltage (Voc) of 48.1 V, a short circuit current (Isc) of 3.1 μA, and a transferred charge of 13.4 nC. The effect of the impact force and contact frequency was systematically studied and the optimal efficiency was confirmed at 5 N and 10 Hz. The 1 cm2 TENG device achieved a peak power density of 903 mW/m2 at 70 MΩ load resistance demonstrated its strong potential for energy harvesting and sensing applications. On simple hand tapping, the device exhibited an output of 200 V and12 μA which was used to charge commercially available capacitor. A smart wearable helmet was designed for real time impact detection by strategically placing the fabricated TENG units in the helmet at different positions. The signals generated from the helmet was processed by a microcontroller and transmitted through a bluetooth module ensuring rapid detection and user notification.