A plant tendril mimic soft actuator with phototunable bending and chiral twisting motion modes

TLDR

Plant tendrils naturally bend and twist in response to light, humidity, and other stimuli, yet existing artificial tendril mimics typically achieve only one deformation mode per ribbon. The study aims to create a single plant‑tendril‑mimic material that can reversibly perform both bending and chiral twisting. A dual‑layer, dual‑composition polysiloxane‑based liquid‑crystal soft actuator is fabricated, enabling the material to switch between bending and chiral twisting by changing the light wavelength from ultraviolet to near‑infrared. The resulting material offers broad prospects for biomimetic control devices.

Abstract

Abstract In nature, plant tendrils can produce two fundamental motion modes, bending and chiral twisting (helical curling) distortions, under the stimuli of sunlight, humidity, wetting or other atmospheric conditions. To date, many artificial plant-like mechanical machines have been developed. Although some previously reported materials could realize bending or chiral twisting through tailoring the samples into various ribbons along different orientations, each single ribbon could execute only one deformation mode. The challenging task is how to endow one individual plant tendril mimic material with two different, fully tunable and reversible motion modes (bending and chiral twisting). Here we show a dual-layer, dual-composition polysiloxane-based liquid crystal soft actuator strategy to synthesize a plant tendril mimic material capable of performing two different three-dimensional reversible transformations (bending versus chiral twisting) through modulation of the wavelength band of light stimuli (ultraviolet versus near-infrared). This material has broad application prospects in biomimetic control devices.