A Triple-Coaxial Soft Fiberbot with All-in-One Sensation–Actuation Capability and High Acid/Alkali-Resistant Stability

Abstract

Intelligent fiberbots integrate selective proprioception and autonomous motility, revealing great application prospects in medical examination and environmental monitoring. However, most fiberbots are limited by the hysteretic sensation–actuation capabilities and often fail in harsh environments (e.g., acid or alkali solutions). To address these issues, this study successfully developed a novel triple-coaxial fibrous composite-derived soft fiberbot. It was fabricated via an artful three-layer (core–middle–sheath) wet-spinning strategy, with each layer serving a specific function. The sheath layer has the properties of acid/alkali-resistant and self-illuminating, the middle layer enables programmable magnetic actuation, and the core layer provides high-selective sensing of mechanics and temperature. In addition, benefiting from its high ductility and seamless interface, the assembled fiberbot exhibits excellent mechanical properties and can maintain continuous visual motion for up to 10h under complex conditions. To further demonstrate the potential of this triple-coaxial fiberbot, several motion patterns are designed by the tactics of three-dimensional printing mold-assisted molding and magnetization. The magnetized fiberbot can not only perform helical propulsion and inchworm-inspired crawling, but also self-sense its own locomotion. Moreover, it can recognize the target states (such as the hardness and temperature) in the acidic stomach and alkaline overheated seawater, achieving a high-fine recognition accuracy of 98.3%. In summary, this work provides a feasible assembly strategy for constructing intelligent fiberbots. These fiberbots combine all-in-one functionalities of programmable actuation, selective sensation, and acid/alkali resistance. This breakthrough opens up broad prospects for future applications in medical examination and harsh environmental monitoring.

Graphical Abstract

Keywords

Triple-coaxial soft fiberbot / Acid/alkali resistance / Multimodal sensations / Magnetic actuation

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Funding

Natural Science Foundation of Jiangxi Province(20224ACB212001)

RIGHTS & PERMISSIONS

Donghua University, Shanghai, China