Unidirectional hybrid composite overload sensors

A purpose-designed, thin-ply interlayer glass/carbon hybrid composite overload sensor concept is presented, which can be used for structural health monitoring (SHM) of composite structures, with potential for safer operation in service. It has been demonstrated that the sensors work satisfactorily and the striped pattern in the composite structure gives a visual indication of overload of the substrate. An analytical model developed here allows for these sensors to be tailored to suit different substrate materials and design strains. The sensors - comprising a single layer of Ultra-High Modulus (UHM) carbon/epoxy and S-glass/epoxy material - were characterised by experimental strain measurements, and finite element analysis (FEA) regarding their accuracy and the effect of their stiffness on the utilized substrate