A paper-based sensor from King Abdullah University of Science and Technology (KAUST) mimics the sensory functions of human skin. The low-cost "Paper Skin" detects external stimuli, including touch, pressure, temperature, acidity, and humidity.

To develop the low-cost sensor, the KAUST engineers employed everyday kitchen materials: aluminum foil, sponges, and tape, for example.

The team used sticky note paper to detect humidity, sponges and wipes to detect pressure, and aluminum foil to detect motion. Coloring a sticky note with an HB pencil allowed the paper to detect acidity levels, and aluminum foil and conductive silver ink were used to detect temperature differences.

The researchers connected the simple paper-based platform to a device that monitored changes in electrical conductivity according to external stimuli.

Increasing levels of humidity, for example, furthered the platform’s ability to store an electrical charge, or its capacitance. Exposing the sensor to an acidic solution similarly increased its resistance, while exposing the sensor to an alkaline solution decreased it.

The KAUST team next hopes to integrate the sensor into medical monitoring systems.