Laser-Processed Nature-Inspired Deformable Structures for Breathable and Reusable Electrophysiological Sensor towards Controllable Home Electronic Appliances and Psychophysiological Stress Monitoring.

Physiological monitoring through skin patch stretchable devices has received extensive attention due to their significant findings in many human-machine interaction applications. In this paper, we present novel nature-inspired kiri-spider serpentine structural designs to sustain mechanical deformations under complex stress environments. Strain-free mechanical structures involving stable high-areal coverage (spiderweb), 3D out-of-plane deformations (kirigami), and 2D stretchable (2D spring) electrodes demonstrated high levels of mechanical loading under various strains, which were verified through theoretical and experimental studies. Alternative to conventional microfabrication procedures, sensors fabricated by a facile, rapid benchtop programmable laser machine enabled the realization of low-cost, high-throughput manufacture, followed by transferring procedures with a nearly 100% yield. For the first time, we demonstrated a laser-processed thin (~10 μm) flexible filamentary patterns embedded within the solution-processed PI to make it compatible with current flexible printed circuit boards (FPCBs) electronics. A patch-based sensor equipped with thin breathable, and sticky nature exhibited remarkable water permeability >20 g h-1m-2 at a thickness of 250 μm. Moreover, the reusability of the sensor patch demonstrated the significance of our patch-based EP sensor. Furthermore, this wearable sensor was successfully implemented to control human-machine interfaces to operate home electronic appliances and monitor mental stress in a pilot study. These advances in novel mechanical architectures with good sensing performances provide new opportunities in wearable smart sensors.