Stretchable Triboelectric–Photonic Smart Skin for Tactile and Gesture Sensing

Abstract

Smart skin is expected to be stretchable and tactile for bionic robots as the medium with the ambient environment. Here, a stretchable triboelectric-photonic smart skin (STPS) is reported that enables multidimensional tactile and gesture sensing for a robotic hand. With a grating-structured metal film as the bioinspired skin stripe, the STPS exhibits a tunable aggregation-induced emission in a lateral tensile range of 0-160%. Moreover, the STPS can be used as a triboelectric nanogenerator for vertical pressure sensing with a maximum sensitivity of 34 mV Pa . The pressure sensing characteristics can remain stable in different stretching conditions, which demonstrates a synchronous and independent sensing property for external stimuli with great durability. By integrating on a robotic hand as a conformal covering, the STPS shows multidimensional mechanical sensing abilities for external touch and different gestures with joints bending. This work has first demonstrated a triboelectric-photonic coupled multifunctional sensing terminal, which may have great applications in human-machine interaction, soft robots, and artificial intelligence.

Mimicking Human and Biological Skins for Multifunctional Skin Electronics

“…The epidermis experiences skin deformation and applied stimuli that can be effectively concentrated to the microridge structures at the epidermal–dermal junction. Inspired by the epidermal–dermal microstructures, several types of e‐skins were demonstrated using interlocked nano/microstructures . Suh and co‐workers demonstrated skin‐attachable flexible strain gauge sensors based on interlocked layers of metal‐coated polyurethane nanofibers, in which contact resistance between nanofibers decreases with applied tactile stimuli ( Figure a) .…”

“…The capacitive ionic e‐skins can exactly perceive finger‐bending motion and autonomously repair cracks or damage on the surface of the e‐skins. The colorimetric skins, which provide intuitive recognition of external stimuli, are another candidate for multifunctional wearable sensors . When colorimetric skins are combined with e‐skins, the integrated system enables both instantaneous perception by color change and accurate perception through analysis of electrical signals.…”

Spiral Steel Wire Based Fiber-Shaped Stretchable and Tailorable Triboelectric Nanogenerator for Wearable Power Source and Active Gesture Sensor

“…4f). Besides, the FST-TENG can be applied as active physiological motion and human-machine interface sensor due to its high sensitivity and rapid response/recovery time for low-frequency movements [43][44][45][46]. Here, it can be embodied in the gesture sensing when constructed into a smart glove, as demonstrated in Fig.…”

Bioinspired Triboelectric Nanogenerators as Self‐Powered Electronic Skin for Robotic Tactile Sensing

“…[7][8][9] E-skin sensors enable the detection and monitoring of proximity, pressure, strain, temperature, etc., or simultaneously monitoring multiple stimuli due to the capability of multimode sensing. [10][11][12] In contrary to conventional sensors, which are based on rigid substrate and functional materials, the flexible and stretchable nature of e-skin sensors demand the development of stretchable materials, structural design and corresponding fabrication schemes to achieve device flexibility or stretchability. [13,14] In the meantime, measurement sensitivity is also a critical metric for e-skin sensors to imitate the sensitive perception capability of human skin.…”