Fig. 14: Fiber-based actuators.
From: Advances and perspectives in fiber-based electronic devices for next-generation soft systems
a Actuation modes and mechanisms of the coiled artificial muscle, driven by electrothermal energy. (RM 82: 1,4-Bis-[4-(6-acryloyloxyhexyloxy) benzoyloxy]-2 methylbenzene; EDDT: 2,2′-(ethylenedioxy) diethanethiol; PETMP: Pentaerythritol tetrakis (3-mercaptopropionate); CNT: Carbon nanotube) b Demonstration of the endoscope-like robot arm and biceps-triceps interaction. This actuator exhibits a 56.9% strain at 14 V. a, b Reprinted with permission314. Copyright 2023, American Chemical Society. c Photographic image of the artificial arm system upon adding the payload from 0.3 to 0.4 N. Twisted and coiled polymer actuator (TCA) is driven electrothermally and achieves 35% contraction with a low power input of only 0.2 W/cm. Reprinted with permission315. Copyright 2024, WILEY-VCH Verlag GmbH & Co. KgaA, Weinheim. d Actuating process of the magnet-driven fiber actuators. Reprinted with permission306. Copyright 2023, WILEY-VCH Verlag GmbH & Co. KgaA, Weinheim. e Snapshots showing the shape change of self-winding fiber actuator (SWFA) from a straight structure to a helically coiled structure upon near infrared (NIR) irradiation. The actuation mechanism is based on the contraction and relaxation of the liquid crystal polymer induced by light. In addition, the SWFA can operate for an extended period without noticeable fatigue, even after 24 h of continuous self-oscillation (1,270,000 cycles). Reprinted with permission316. Copyright 2021, Springer Nature. f Time-lapse snapshots exhibited the salt accumulation during the desalination process of the original RGO@HHF and g double-twisted RGO@HHF. This is attributed to the dual driving responsiveness of the fiber actuator to water and light. (RGO@HHF: Hollow hydrogel fiber loaded with reduced graphene oxide). f, g Reprinted with permission317. Copyright 2023, WILEY-VCH Verlag GmbH & Co. KgaA, Weinheim.
