An Interdigital Strain Sensor Through Laser Carbonization of PI and PDMS Transfer

Additive methods using inks have attracted significant attention for printing sensors. Laser carbonization of polyimide is an ink-less alternative. In this paper laser carbonization and transfer to polydimethylsiloxane (PDMS) are used for the realization of interdigital electrode-based impedance strain sensors. These were fabricated employing high-resolution laser engraver optics and are characterized under mechanical deformations with an impedance analyzer to assess their sensitivity. The sensors achieved appreciable strain sensitivities (~1%/N) that improve with increasing excitation frequency (500 Hz to 50 kHz), demonstrating the applicability of the sensor and the fabrication process for strain sensing.