Fabrication and Characterization of Highly Deformable Artificial Muscle Fibers Based on Liquid Crystal Elastomers

2020 ◽  
Vol 88 (4) ◽  
Author(s):  
Haiqing Lu ◽  
Zhanan Zou ◽  
Xingli Wu ◽  
Chuanqian Shi ◽  
Jianliang Xiao
Keyword(s):  
Liquid Crystal ◽  
Low Cost ◽  
Muscle Fibers ◽  
Artificial Muscle ◽  
Electric Heating ◽  
Heating Time ◽  
Soft Systems ◽  
Screen Printing Technique ◽  
Liquid Crystal Elastomers ◽  
Pulling Force

Abstract Artificial muscles have important applications in areas ranging from robotics to prosthetics and medical devices. In this study, highly deformable artificial muscle fibers that utilize superior actuating properties of liquid crystal elastomers and liquid-like deformability of liquid metal are reported. An effective and low-cost fabrication approach using screen printing technique is developed. The actuating properties of the artificial muscle fibers, including the dependence of temperature, contraction strain, and pulling force of the artificial muscle fiber on electric heating current and heating time, are characterized. The results could provide important guidance to design and for development of soft systems that utilize the actuating mechanisms of liquid crystal elastomers.

Smart artificial muscle actuators: Liquid crystal elastomers with integrated temperature feedback

2015 ◽  
Vol 231 ◽  
pp. 44-51 ◽  
Author(s):  
S. Petsch ◽  
R. Rix ◽  
B. Khatri ◽  
S. Schuhladen ◽  
P. Müller ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Artificial Muscle ◽  
Temperature Feedback ◽  
Liquid Crystal Elastomers ◽  
Muscle Actuators

Artificial muscles based on liquid crystal elastomers

2006 ◽  
Vol 364 (1847) ◽  
pp. 2763-2777 ◽  
Author(s):  
Min-Hui Li ◽  
Patrick Keller
Keyword(s):  
Liquid Crystal ◽  
Main Chain ◽  
Uv Light ◽  
Shape Change ◽  
Artificial Muscle ◽  
Isotropic Phase ◽  
Artificial Muscles ◽  
Stimuli Responsive ◽  
Liquid Crystal Elastomers ◽  
The Individual

This paper presents our results on liquid crystal (LC) elastomers as artificial muscle, based on the ideas proposed by de Gennes. In the theoretical model, the material consists of a repeated series of main-chain nematic LC polymer blocks, N, and conventional rubber blocks, R, based on the lamellar phase of a triblock copolymer RNR. The motor for the contraction is the reversible macromolecular shape change of the chain, from stretched to spherical, that occurs at the nematic-to-isotropic phase transition in the main-chain nematic LC polymers. We first developed a new kind of muscle-like material based on a network of side-on nematic LC homopolymers. Side-on LC polymers were used instead of main-chain LC polymers for synthetic reasons. The first example of these materials was thermo-responsive, with a typical contraction of around 35–45% and a generated force of around 210 kPa. Subsequently, a photo-responsive material was developed, with a fast photochemically induced contraction of around 20%, triggered by UV light. We then succeeded in preparing a thermo-responsive artificial muscle, RNR, with lamellar structure, using a side-on nematic LC polymer as N block. Micrometre-sized artificial muscles were also prepared. This paper illustrates the bottom-up design of stimuli-responsive materials, in which the overall material response reflects the individual macromolecular response, using LC polymer as building block.

Mechano‐Optical Sensors Fabricated with Multilayered Liquid Crystal Elastomers Exhibiting Tunable Deformation Recovery

2021 ◽  
pp. 2104702
Author(s):  
Kyohei Hisano ◽  
Seiya Kimura ◽  
Kyosun Ku ◽  
Tomoki Shigeyama ◽  
Norihisa Akamatsu ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Optical Sensors ◽  
Liquid Crystal Elastomers ◽  
Deformation Recovery

scholarly journals From Bend to Splay Dominated Elasticity in Nematics

Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 831
Author(s):  
Davide Revignas ◽  
Alberta Ferrarini
Keyword(s):  
Liquid Crystal ◽  
Nematic Phase ◽  
Low Cost ◽  
Elastic Behavior ◽  
Computational Investigation ◽  
Apical Angle ◽  
Polar Order ◽  
The Past ◽  
Bend Angles ◽  
Analogous Effect

In the past decade, much evidence has been provided for an unusually low cost for bend deformations in the nematic phase of bent-core mesogens and bimesogens (liquid crystal dimers) having a bent shape on average. Recently, an analogous effect was observed for the splay mode of bent-core mesogens with an acute apical angle. Here, we present a systematic computational investigation of the Frank elastic constants of nematics made of V-shaped particles, with bend angles ranging from acute to obtuse. We show that by tuning this angle, the elastic behavior switches from bend dominated (K33>K11) to splay dominated (K11>K33), with anomalously low values of the splay and the bend constant, respectively. This is related to a change in the shape polarity of particles, which is associated with the emergence of polar order, longitudinal for splay and transversal for bend deformations. Crucial to this study is the use of a recently developed microscopic elastic theory, able to account for the interplay of mesogen morphology and director deformations.

Thermomechanically active electrodes power work-dense soft actuators

Soft Matter ◽  
2021 ◽  
Author(s):  
Angel Martinez ◽  
Arul Clement ◽  
Junfeng Gao ◽  
Julia Kocherzat ◽  
Mohsen Tabrizi ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Liquid Metal ◽  
Chain Extender ◽  
Design Work ◽  
Liquid Crystal Elastomers ◽  
Soft Actuators ◽  
Dense Liquid

The effect of chain extender structure and composition on the properties of liquid crystal elastomers (LCE) is presented. Compositions are optimized to design work-dense liquid metal LCE composites that are operated with 100 mW power.

Effect of stretching angle on the stress plateau behavior of main-chain liquid crystal elastomers

Soft Matter ◽  
2021 ◽  
Vol 17 (11) ◽  
pp. 3128-3136
Author(s):  
Suzuka Okamoto ◽  
Shinichi Sakurai ◽  
Kenji Urayama
Keyword(s):  
Liquid Crystal ◽  
Main Chain ◽  
Stress Plateau ◽  
Liquid Crystal Elastomer ◽  
Ultimate Elongation ◽  
Liquid Crystal Elastomers

Stretching angle for a main-chain liquid crystal elastomer has pronounced effects on the width of the stress plateau as well as the ultimate elongation, while it has no effect on the plateau height.

Electrostatic bellow muscle actuators and energy harvesters that stack up

2021 ◽  
Vol 6 (51) ◽  
pp. eaaz5796
Author(s):  
I. D. Sîrbu ◽  
G. Moretti ◽  
G. Bortolotti ◽  
M. Bolignari ◽  
S. Diré ◽  
...  
Keyword(s):  
High Performance ◽  
High Reliability ◽  
Low Cost ◽  
Artificial Muscle ◽  
Pressure Head ◽  
Robotic Systems ◽  
Maximum Pressure ◽  
Term Operation ◽  
Energy Harvesters ◽  
Out Of Plane

Future robotic systems will be pervasive technologies operating autonomously in unknown spaces that are shared with humans. Such complex interactions make it compulsory for them to be lightweight, soft, and efficient in a way to guarantee safety, robustness, and long-term operation. Such a set of qualities can be achieved using soft multipurpose systems that combine, integrate, and commute between conventional electromechanical and fluidic drives, as well as harvest energy during inactive actuation phases for increased energy efficiency. Here, we present an electrostatic actuator made of thin films and liquid dielectrics combined with rigid polymeric stiffening elements to form a circular electrostatic bellow muscle (EBM) unit capable of out-of-plane contraction. These units are easy to manufacture and can be arranged in arrays and stacks, which can be used as a contractile artificial muscle, as a pump for fluid-driven soft robots, or as an energy harvester. As an artificial muscle, EBMs of 20 to 40 millimeters in diameter can exert forces of up to 6 newtons, lift loads over a hundred times their own weight, and reach contractions of over 40% with strain rates over 1200% per second, with a bandwidth over 10 hertz. As a pump driver, these EBMs produce flow rates of up to 0.63 liters per minute and maximum pressure head of 6 kilopascals, whereas as generator, they reach a conversion efficiency close to 20%. The compact shape, low cost, simple assembling procedure, high reliability, and large contractions make the EBM a promising technology for high-performance robotic systems.

Sign in / Sign up

Export Citation Format

Share Document