Minimally Intrusive SHM Systems Using Piezoelectric Nanofibers in Composite Laminates

Abstract

This work presents the development of a self-sensing Carbon Fiber Reinforced Polimer (CFRP) laminate embedding P(VDF-TrFE) nanofibers for real-time impact detection and localization. Four nanostructured sensors were embedded within the midplane of cross-ply laminates and compared against laminates incorporating commercial PZT sensors. A probabilistic impact localization algorithm based on Gaussian Process Regression and differential Time of Arrival (dToA) measurements were implemented. While PZT sensors exhibited higher localization accuracy (RMSE=2.32 cm) compared to nanofiber-based sensors (RMSE=3.37 cm), they caused more severe interfacial damage under low-velocity impacts. In contrast, the nanostructured sensors confined damage to the polymeric interlayer, preserving the CFRP integrity. The results highlight the potential of nanofiber-based sensing layers as a scalable, minimally invasive solution for Structural Health Monitoring in aerospace composites.