Shape morphing mechanical metamaterials through reversible plasticity

Science Robotics, Год журнала: 2022, Номер 7(63)

Опубликована: Фев. 9, 2022

Biological organisms such as the octopus can reconfigure their shape and properties to perform diverse tasks. However, soft machines struggle achieve complex configurations, morph into support loads, go between multiple states reversibly. Here, we introduce a multifunctional shape-morphing material with reversible rapid polymorphic reconfigurability. We couple elastomeric kirigami an unconventional plasticity mechanism in metal alloys rapidly ( < 0.1 seconds) flat sheets complex, load-bearing shapes, reversibility self-healing through phase change. This composite overcomes trade-offs deformability capacity eliminates power requirements sustain reconfigured shapes. demonstrate this integration onboard control, motors, create robotic morphing drone, which autonomously transforms from ground air vehicle underwater machine, be reversibly deployed collect cargo.

Язык: Английский

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Human-muscle-inspired single fibre actuator with reversible percolation

Nature Nanotechnology, Год журнала: 2022, Номер 17(11), С. 1198 - 1205

Опубликована: Окт. 27, 2022

Abstract Artificial muscles are indispensable components for next-generation robotics capable of mimicking sophisticated movements living systems. However, an optimal combination actuation parameters, including strain, stress, energy density and high mechanical strength, is required their practical applications. Here we report mammalian-skeletal-muscle-inspired single fibres bundles with large strong contractive actuation. The use exfoliated graphene fillers within a uniaxial liquid crystalline matrix enables photothermal work capacity rapid response. Moreover, the reversible percolation induced by thermodynamic conformational transition mesoscale structures can be in situ monitored electrical switching. Such dynamic behaviour effectively strengthens properties actuator fibres, particularly contracted state, enabling mammalian-muscle-like reliable Taking advantage mechanically compliant fibre structure, smart actuators readily integrated into as well high-power soft light-driven remote control.

Язык: Английский

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3D‐Printed Photoresponsive Liquid Crystal Elastomer Composites for Free‐Form Actuation

Advanced Functional Materials, Год журнала: 2022, Номер 33(4)

Опубликована: Ноя. 11, 2022

Abstract Direct ink writing of liquid crystal elastomers (LCEs) offers a new opportunity to program geometries for wide variety shape transformation modes toward applications such as soft robotics. So far, most 3D‐printed LCEs are thermally actuated. Herein, 3D‐printable photoresponsive gold nanorod (AuNR)/LCE composite is developed, allowing photothermal actuation the structures with AuNR low 0.1 wt.%. It shown that printed filament has superior response 27% strain upon irradiation near‐infrared (NIR) light (808 nm) at 1.4 W cm −2 (corresponding 160 °C) under optimal printing conditions. The can be globally or locally actuated into different shapes by controlling area exposed NIR laser. Taking advantage customized enabled 3D and ability control light, light‐responsive robot demonstrated climb on ratchet surface maximum speed 0.284 mm s −1 (on flat surface) 0.216 30° titled surface), respectively, corresponding 0.428 0.324 body length per min, large mass (0.23 g) thickness (1 mm).

Язык: Английский

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Bioinspired Liquid Crystalline Spinning Enables Scalable Fabrication of High‐Performing Fibrous Artificial Muscles

Advanced Materials, Год журнала: 2023, Номер 35(16)

Опубликована: Фев. 22, 2023

Leveraging liquid crystal elastomers (LCEs) to realize scalable fabrication of high-performing fibrous artificial muscles is particular interest because these active soft materials can provide large, reversible, programmable deformations upon environmental stimuli. High-performing LCEs require the used processing technology enable shaping into micro-scale fine fibers as thin possible while achieving macroscopic LC orientation, which however remains a daunting challenge. Here, bioinspired spinning reported that allows for continuous, high-speed production (fabrication speed up 8400 m h-1 ) and aligned LCE microfibers combined with rapid deformation (actuation strain rate 810% s-1 ), powerful actuation stress 5.3 MPa), high response frequency (50 Hz), long cycle life (250 000 cycles without obvious fatigue). Inspired by crystalline spiders takes advantage multiple drawdowns align their dragline silks, internal drawdown via tapered-wall-induced-shearing external mechanical stretching are employed shape long, thin, desirable performances, few technologies achieve. This capable would benefit development smart fabrics, intelligent wearable devices, humanoid robotics, other areas.

Язык: Английский

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Highly Stretchable and Conductive MXene‐Encapsulated Liquid Metal Hydrogels for Bioinspired Self‐Sensing Soft Actuators

Advanced Functional Materials, Год журнала: 2023, Номер 34(7)

Опубликована: Ноя. 3, 2023

Abstract Advanced sensation and actuation abilities of various living organisms in nature have inspired researchers to design bioinspired self‐sensing soft actuators. However, the majority conventional actuators primarily possess capabilities while lacking a real‐time sensing signal feedback. Here, promising strategy is reported develop highly stretchable conductive hydrogels for actuators, which integrate strain‐sensing functions into single materials system. The are designed fabricated by situ copolymerization amino‐functionalized MXene‐encapsulated liquid metal nanodroplets (LM@A‐MXene) poly( N ‐isopropylacrylamide) with controllable activated nanogels as nano‐cross‐linkers. resulting hydrogel presents compacted conducting network porous microstructure, giving rise robust integration high conductivity, excellent strain sensitivity, broad stretchability, stability, fast response speed. Interestingly, gradient structure, formed self‐precipitation LM@A‐MXene, endows shape‐programmable actuation, light‐driven remote control, function. As proof‐of‐concept application, gripper based on developed, can not only grasp, lift, release objects, but also perceive every movement state monitoring resistance changes. proposed actuator offer new insights developing smart robotics other artificial intelligent devices.

Язык: Английский

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A modular strategy for distributed, embodied control of electronics-free soft robots

Science Advances, Год журнала: 2023, Номер 9(27)

Опубликована: Июль 7, 2023

Robots typically interact with their environments via feedback loops consisting of electronic sensors, microcontrollers, and actuators, which can be bulky complex. Researchers have sought new strategies for achieving autonomous sensing control in next-generation soft robots. We describe here an electronics-free approach robots, whose compositional structural features embody the sensing, control, actuation loop bodies. Specifically, we design multiple modular units that are regulated by responsive materials such as liquid crystal elastomers. These modules enable robot to sense respond different external stimuli (light, heat, solvents), causing changes robot's trajectory. By combining types modules, complex responses achieved, logical evaluations require events occur environment before action is performed. This framework embodied offers a strategy toward robots operate uncertain or dynamic environments.

Язык: Английский

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Active terahertz beam steering based on mechanical deformation of liquid crystal elastomer metasurface

Light Science & Applications, Год журнала: 2023, Номер 12(1)

Опубликована: Янв. 4, 2023

Abstract Active metasurfaces are emerging as the core of next-generation optical devices with their tunable responses and flat-compact topography. Especially for terahertz band, active have been developed fascinating chopping compressive sensing imaging. However, performance regulation by changing dielectric parameters integrated functional materials exhibits severe limitations parasitic losses. Here, we introduce a C-shape-split-ring-based phase discontinuity metasurface liquid crystal elastomer substrate infrared modulation wavefront. Line-focused light is applied to manipulate deflection substrate, enabling controllable broadband wavefront steering maximum output angle change 22° at 0.68 THz. Heating another control method also investigated compared control. We further demonstrate beam steerer, frequency modulator, splitter, which highly desired in wireless communication imaging systems. The proposed scheme demonstrates promising prospects mechanically deformable metasurfaces, thereby paving path development reconfigurable metasurfaces.

Язык: Английский

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Magnetic Microrobots with Folate Targeting for Drug Delivery

Cyborg and Bionic Systems, Год журнала: 2023, Номер 4

Опубликована: Янв. 1, 2023

Untethered microrobots can be used for cargo delivery (e.g., drug molecules, stem cells, and genes) targeting designated areas. However, it is not enough to just reach the lesion site, as some drugs only play best therapeutic effect within cells. To this end, folic acid (FA) was introduced into in work a key mediate endocytosis of The here were fabricated with biodegradable gelatin methacryloyl (GelMA) modified magnetic metal–organic framework (MOF). porous structure MOF hydrogel network polymerized GelMA loading FA anticancer doxorubicin (DOX) respectively. Utilizing property MOF, these gather around site navigation fields. combination effects substantially improve efficiency microrobots. result shows that cancer cells inhibition rate up 93%, while ones without 78%. introduction useful method transportation ability microrobots, providing meaningful reference further research.

Язык: Английский

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Scalable functionalized liquid crystal elastomer fiber soft actuators with multi-stimulus responses and photoelectric conversion

Materials Horizons, Год журнала: 2023, Номер 10(7), С. 2587 - 2598

Опубликована: Янв. 1, 2023

Liquid crystal elastomer (LCE) fibers exhibit large deformation and reversibility, making them an ideal candidate for soft actuators. It is still challenging to develop a scalable strategy endow fiber actuators with photoelectric functions achieve tailorable photo-electro-thermal responsiveness rapid actuation deformation. Herein, we fabricated multiresponsive actuator that consists of LCE long obtained by continuous dry spinning further coated it polydopamine (PDA)-modified MXene ink. The designed PDA@MXene-integrated used shape-deformable multi-trigger can be photo- electro-thermally actuated. proposed combines excellent photothermal long-term electrically conductive PDA@MXene shape-morphing fiber, enabling their robust mechanical flexibility, multiple fast responses (∼0.4 s), stable (∼60%). As proof-of-concept, present near-infrared light-driven artificial muscle lift 1000 times the weight intelligent circuit switch controllability (∼0.1 s). Importantly, adaptive smart window system integrates energy harvesting/conversion ingeniously constructed integration propellable curtain woven solar cells. This work provide insights into development advanced materials toward robotics, sustainable savings beyond.

Язык: Английский

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Active Textile Fabrics from Weaving Liquid Crystalline Elastomer Filaments

Advanced Materials, Год журнала: 2023, Номер 35(14)

Опубликована: Янв. 14, 2023

Active fabrics, responding autonomously to environmental changes, are the "Holy Grail" of development smart textiles. Liquid crystal elastomers (LCEs) promise be base materials for large-stroke reversible actuation. The mechanical behavior LCEs matches almost exactly human muscle. Yet, it has not been possible produce filaments from that will suitable standard textile production methods, such as weaving. Based on recent LCE fibers, here, crafting active fabrics incorporating yarn, woven a loom, giving control over weave density and structure, is presented. Two types yarns (soft stiff) their incorporation into several weaving patterns tested, "champions" identified: twill pattern with stiffer yarn shows greatest blocking force 1-2 N cm-1 , weft rib 10% actuation strain repeated heating cycles. Reversible 3D shape changes fabric utilize circular lead cone shapes upon heating. seamless combination rich portfolio existing passive can transformative in creating new stimuli-responsive actuating

Язык: Английский

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