Star-nose-inspired multi-mode sensor for anisotropic motion monitoring

Highlights: • A star-nose-inspired multi-mode sensor has been designed and fabricated by electrospinning and chemical silver coating. • The bio-inspired sensor demonstrates ultra-light, ultra-thin, and high sensitivity (Gauge Factor (GF) ~ 4000) characteristics. • The anisotropic ability for omnidirectional sensing of human motion is realized by assembling two functional layers laterally. Stretchable and twistable sensors attract much attention due to their excellent flexibility, stability, and sensitivity for most wearable devices. Star nasal moles in nature possess a flexible and highly sensitive nose that is composed of dozens of epidermal appendages or rays densely covered with small organs, which provides us inspiration for fabricating highly sensitive sensors. Herein, we present a strategy to build a star-nose-inspired sensor with stretchable and twistable structure, where the nose's ray-like parallel polyimide films were fabricated by electrospinning and chemical silver coating. The sensor is finally encapsulated in PDMS and its sensitivity is significantly improved due to the design of bio-inspired parallel films. The bio-inspired sensor finally exhibits ultra-light, ultra-thin, and high sensitivity (Gauge Factor (GF) ~ 4000) characteristics, ensuring a perfect fit for human skin to achieve stretch, twist, and pressure detection functions. At last, an anisotropic sensor for omnidirectionally sensing human motions was built by crosswise assembling two of functional layers. This study highlights interesting possibilities for bioinspired sensors, with integrated light, thin, stretchable, twistable, and anisotropic features for wearable devices for monitoring human movement and personal health.