All-Inkjet Printed Strain Sensors

Low cost approaches for the direct printing of electric components usually require two different technologies for conductive patterns and functional layers. Conductive structures (wires, coils, and electrodes) are usually screen printed while low cost inkjet systems can be used for the realization of functional layers (e.g., resistive and dielectric film, sensing areas). This hybrid approach, motivated by the poor availability of conductive inks compatible with low cost printing systems, does not fulfill requirements of rapid prototyping. In this paper, the realization of strain gauge sensors by a low cost all-inkjet process exploiting a Metalon water-based silver ink by Novacentrix is presented as a possible and convenient approach for the rapid prototyping of sensors by cheap inkjet printing techniques. The latter could be dramatic for specific contexts where short developing times and low cost features of printing equipments are mandatory, such as lab scale prototyping and research laboratories. The experimental results confirm both the suitability of the proposed approach and expected performances of lab-scale prototypes developed.