Flexible multimodal sensor inspired by human skin based on hair-type flow, temperature, and pressure

Flexible electronic circuits when integrated with different sensors to mimic the human skin can be referred to as E-skin. E-skin can be used for the monitoring of human health, human-machine interface and humanoids. To mimic skin, a variety of sensors have been studied, including those sensitive to different pressures, temperatures, flows, and strain and humidity levels. Herein, we demonstrate a multifunctional sensor encompassed in a single pixel which is inspired by human skin. The proposed device contains a pressure sensor, a temperature sensor and a piezoresistive hair-type flow sensor, the latter of which is fabricated using mixture of carbon nanotubes and polydimethylsiloxane piezoresistive materials. Additionally, the temperature sensor is printed by means of inkjet printing with MWCNT and Ag nanoparticle ink. Finally, all three sensors are vertically stacked to mimic the human skin, demonstrating interference-free characteristics. This study provides a new and cost-effective approach for multimodal sensor applications.