A printed electrical impedance tomography sensor for detection of damage in composites

This paper proposes a new printed electrical impedance tomography (EIT) sensor for detection of damage in composite structure. The EIT sensor consists of a sensing area and related electrical circuits. It is directly printed on the surface of composite structure by a layer-by-layer screen printing process with graphene-doped carbon ink and silver ink. By injecting tiny currents into the EIT sensor and measuring the corresponding boundary voltages, damage information can be obtained by inverse analysis to reconstruct the distribution of conductivity change caused by damage. It has the potential to quantitatively identify the locations and sizes of multiple damage without any prior knowledge. Experimental results on a glass fiber reinforced polymer (GFRP) plate with different number of simulated damage have demonstrated the effectiveness of the printed sensor itself and the related damage detection method.