Characterization of low-cost inkjet printed-photonic cured strain gauges for remote sensing and structural monitoring applications

In the present work, cost-effective strain gauges were fabricated by using inkjet printing and photonic curing on flexible and recyclable PET substrates. Ohmic resistance (a.k.a. DC resistance) (R₀) and complex electrical impedance (Z) as a function of test frequency were characterized, respectively, with the state-of-the-art electronic testing equipment. For the fabrication process, commercially available silver nanoparticle (AgNP) inks and substrates were used. In order to validate the in-house cantilever beam measurement setup and devices, first, commercially available metallic foil strain gauges (with the provided gauge factor GF=2.0 by the manufacturer) were tested at different locations. Thereafter, the printed strain gauges were investigated with several repetitions at different measurement locations. The measurement results demonstrated an affordable, rapid, and tailorable design and repeatable fabrication approach for strain gauges with GF_avg~6.6, which has potential applications in remote sensing and structural monitoring applications.