Work

Gourd‐Inspired Design of Unit Cell with Multiple Gradients for Physiological‐Range Pressure Sensing

Year: 2025

Type: article

Abstract: ABSTRACT Reliable decoding of tactile information in flexible electronics requires piezoresistive sensors to combine high sensitivity with linear response across physiological pressures. In this work, we show that co‐optimization of sensitivity and linearity can be solved using gourd‐shaped micro‐dome arrays (GSDAs) that implement three coordinated gradients (modulus, conductivity and geometry) within a single cell. The unit cell is composed of a solid upper dome (smaller diameter) with lower conductivity, and a porous lower dome (larger diameter) with higher conductivity. Upon mechanical loading, the large modulus contrast drives the upper dome to embed into the porous layer, rapidly enlarging real contact area and shortening electrical tunnelling gaps. Furthermore, the embedding process of upper micro‐dome (MD) yields a series‐to‐parallel electrical transition that suppresses early signal saturation. The optimized device remains linear response up to 210 kPa with a sensitivity of 534.9 kPa −1 . Establishing consistent intensity mapping, we show that the GSDA can serve as either sensing unit, or arrayed assembly, for diverse applications such as tactile monitoring, password encoding, Morse codes, robotic control, and effective sign‐language recognition. This modulation strategy on a single sensing unit provides a valuable route for the development of flexible sensors with simultaneous realization of high sensitivity and wide linear range.

Source: Advanced Functional Materials

DOI: 10.1002/adfm.202527243