Highly flexible and transparent dielectric elastomer actuators using silver nanowire and carbon nanotube hybrid electrodes

Electrodes consisting of silver nanowires and carbon nanotubes enable a dielectric elastomer actuator to become highly stretchable and optically transparent.

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Outstanding electromagnetic interference shielding of silver nanowires: comparison with carbon nanotubes

RSC Advances ◽

10.1039/c5ra08118a ◽

2015 ◽

Vol 5 (70) ◽

pp. 56590-56598 ◽

Cited By ~ 39

Author(s):

Mohammad Arjmand ◽

Aref Abbasi Moud ◽

Yan Li ◽

Uttandaraman Sundararaj

Keyword(s):

Carbon Nanotubes ◽

Carbon Nanotube ◽

Electrical Properties ◽

Electromagnetic Interference ◽

Silver Nanowires ◽

Silver Nanowire ◽

Electromagnetic Interference Shielding ◽

Commercial Carbon

Synthesized silver nanowire/polystyrene nanocomposites showed superior electrical properties to commercial carbon nanotube/polystyrene nanocomposites at high filler loadings. This was ascribed to the higher metallic nature of silver nanowires.

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Dielectric Elastomer Actuators with Carbon Nanotube Electrodes Painted with a Soft Brush

Actuators ◽

10.3390/act7030051 ◽

2018 ◽

Vol 7 (3) ◽

pp. 51 ◽

Cited By ~ 11

Author(s):

Hiroki Shigemune ◽

Shigeki Sugano ◽

Jun Nishitani ◽

Masayuki Yamauchi ◽

Naoki Hosoya ◽

...

Keyword(s):

Carbon Nanotube ◽

Electronic Properties ◽

Large Deformation ◽

Dielectric Elastomer ◽

Dielectric Elastomer Actuator ◽

Dielectric Elastomer Actuators ◽

Multiple Trials

We propose a simple methodology to paint carbon nanotube (CNT) powder with a soft brush onto an elastomer. A large deformation of dielectric elastomer actuator (DEA) occurs according to the small constraint of the electrodes. Uniform painting with a soft brush leads to a stable deformation, as demonstrated by the results of multiple trials. Unexpectedly, painting with a soft brush results in aligned materials on the elastomer. The oriented materials demonstrate anisotropic mechanical and electronic properties. This simple methodology should help realize innovative DEA applications.

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Properties of a Dielectric Elastomer Actuator Modified by Dispersion of Functionalised Carbon Nanotubes

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.79.41 ◽

2012 ◽

Vol 79 ◽

pp. 41-46 ◽

Cited By ~ 1

Author(s):

Fabia Galantini ◽

Sabrina Bianchi ◽

Valter Castelvetro ◽

Irene Anguillesi ◽

Giuseppe Gallone

Keyword(s):

Carbon Nanotubes ◽

Dielectric Constant ◽

Mechanical Performance ◽

Broad Class ◽

Dielectric Elastomer ◽

Low Dielectric ◽

Dielectric Elastomer Actuators ◽

Electromechanical Transduction ◽

The Matrix ◽

Simple Matrix

Among the broad class of electro-active polymers, dielectric elastomer actuators represent a rapidly growing technology for electromechanical transduction. In order to further develop this applied science, the high driving voltages currently needed must be reduced. For this purpose, one of the most promising and adopted approach is to increase the dielectric constant while maintaining both low dielectric losses and high mechanical compliance. In this work, a dielectric elastomer was prepared by dispersing functionalised carbon nanotubes into a polyurethane matrix and the effects of filler dispersion into the matrix were studied in terms of dielectric, mechanical and electro-mechanical performance. An interesting increment of the dielectric constant was observed throughout the collected spectrum while the loss factor remained almost unchanged with respect to the simple matrix, indicating that conductive percolation paths did not arise in such a system. Consequences of the chemical functionalisation of carbon nanotubes with respect to the use of unmodified filler were also studied and discussed along with rising benefits and drawbacks for the whole composite material.

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Trajectory control and random vibration control of nonlinear system with dielectric elastomer actuator

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x18770867 ◽

2018 ◽

Vol 29 (11) ◽

pp. 2424-2436 ◽

Cited By ~ 2

Author(s):

Yanping Tian ◽

Yong Wang ◽

Xiaoling Jin ◽

Zhilong Huang

Keyword(s):

Nonlinear System ◽

Control Strategy ◽

Primary Structure ◽

Equilibrium Position ◽

Random Vibration ◽

Dielectric Elastomer ◽

Control Technique ◽

Dynamic Programming Principle ◽

Dielectric Elastomer Actuator ◽

Dielectric Elastomer Actuators

Dielectric elastomer actuators have gained extensive attention in scientific and industrial communities with the rapid development of soft robot technology. There still remain some questions on the control aspect of nonlinear system with dielectric elastomer actuator. The first is whether the soft actuator can successfully drive the primary structure to track an arbitrary prescribed trajectory. The second is how to suppress the random vibration around the equilibrium position when the primary structure is disturbed by external excitation. This article seeks the answers for these two questions. By directly solving the governing equation of motion, an open-loop control technique is designed to track a prescribed trajectory. The effectiveness of the trajectory tracking technique is investigated and the limitation is illustrated by the influence of inertia of the primary structure. Based on the stochastic averaging of energy envelope and stochastic dynamic programming principle, a clipped control strategy is proposed by slightly adjusting the voltage in real time to suppress the random vibration around the equilibrium position. The good effectiveness and high robustness of the clipped control strategy are verified numerically. This work may provide some guidelines for the control aspect of nonlinear systems with dielectric elastomer actuators.

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Carbon Nanotubes: Highly Stretchable Supercapacitors via Crumpled Vertically Aligned Carbon Nanotube Forests (Adv. Energy Mater. 22/2019)

Advanced Energy Materials ◽

10.1002/aenm.201970082 ◽

2019 ◽

Vol 9 (22) ◽

pp. 1970082 ◽

Cited By ~ 1

Author(s):

Changyong Cao ◽

Yihao Zhou ◽

Stephen Ubnoske ◽

Jianfeng Zang ◽

Yunteng Cao ◽

...

Keyword(s):

Carbon Nanotubes ◽

Carbon Nanotube ◽

Highly Stretchable ◽

Vertically Aligned ◽

Carbon Nanotube Forests ◽

Energy Mater

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A highly stretchable and transparent silver nanowire/thermoplastic polyurethane film strain sensor for human motion monitoring

Inorganic Chemistry Frontiers ◽

10.1039/c9qi00989b ◽

2019 ◽

Vol 6 (11) ◽

pp. 3119-3124 ◽

Cited By ~ 10

Author(s):

Runfei Wang ◽

Wei Xu ◽

Wenfeng Shen ◽

Xiaoqing Shi ◽

Jian Huang ◽

...

Keyword(s):

Silver Nanowires ◽

Thermoplastic Polyurethane ◽

Human Motion ◽

Strain Sensors ◽

Silver Nanowire ◽

Transparent Film ◽

Polyurethane Film ◽

Highly Stretchable ◽

Human Motion Monitoring ◽

Human Motions

Transparent film strain sensors based on silver nanowires and thermoplastic polyurethane are promising candidates for detecting various human motions and monitoring the mass of some kinetic objects.

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Modeling and Actuation Performance Analysis of Conically-Shaped Dielectric Electroactive Polymer Actuator

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.633-634.250 ◽

2014 ◽

Vol 633-634 ◽

pp. 250-256

Author(s):

Yin Long Zhu ◽

Hong Pin Zhou ◽

Hua Ming Wang

Keyword(s):

Dielectric Elastomer ◽

Force Output ◽

Energy Potential ◽

Principal Stresses ◽

Dielectric Elastomer Actuator ◽

Design And Optimization ◽

Dielectric Elastomer Actuators ◽

Proposed Model ◽

Polymer Actuator ◽

Potential Applications

Dielectric elastomer actuators (DEAs) represent one class of electroactive polymers that have already demonstrated excellent performances and show potential applications in many fields. In this paper, we present a simplified conically-shaped dielectric elastomer actuator model to explore the effects of various preloads and actuation voltages on both the actuation displacement and force output of DEA. The strain energy potential of Yeoh is used and the viscoelasticity is also taken into account. Using the developed model, the numerical results of DEA including the actuation displacement, the distribution of the principal stretch ratios and principal stresses in the membrane and the force output can be obtained. With different preloads and actuation voltages, the actuation characteristic of conically-shaped dielectric elastomer actuator is explored experimentally and validates the results determined from the proposed model. The proposed model can be used for the design and optimization of conically-shaped dielectric elastomer actuator.

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Linear-Quadratic Regulator for Control of Multi-Wall Carbon Nanotube/Polydimethylsiloxane Based Conical Dielectric Elastomer Actuators

Actuators ◽

10.3390/act9010018 ◽

2020 ◽

Vol 9 (1) ◽

pp. 18

Author(s):

Titus Mulembo ◽

Waweru Njeri ◽

Gakuji Nagai ◽

Hirohisa Tamagawa ◽

Keishi Naito ◽

...

Keyword(s):

Carbon Nanotube ◽

Rise Time ◽

Electromechanical Coupling ◽

Linear Quadratic Regulator ◽

Fast Response ◽

Dielectric Elastomer ◽

Soft Robotics ◽

Artificial Muscles ◽

Linear Quadratic ◽

Dielectric Elastomer Actuators

Conventional rigid actuators, such as DC servo motors, face challenges in utilizing them in artificial muscles and soft robotics. Dielectric elastomer actuators (DEAs) overcome all these limitations, as they exhibit complex and fast motions, quietness, lightness, and softness. Recently, there has been much focus on studies of the DEAs material’s non-linearity, the non-linear electromechanical coupling, and viscoelastic behavior of VHB and silicone-based conical DEAs having compliant electrodes that are based on graphite powder and carbon grease. However, the mitigation of overshoot that arises from fast response conical DEAs made with solid electrodes has not received much research focus. In this paper, we fabricated a conical configuration of multi-walled carbon nanotube/polydimethylsiloxane (MWCNT/PDMS) based DEAs with a rise time of 10 ms, and 50% peak overshoot. We developed a full feedback state-based linear-quadratic regulator (LQR) having Luenberger observer to mitigate the DEAs overshoot in both the voltage ON and OFF instances. The cone DEA’s model was identified and a stable and well-fitting transfer function with a fit of 94% was obtained. Optimal parameters Q = 70,000, R = 0.1, and Q = 7000, R = 0.01 resulted in the DEA response having a rise time value of 20 ms with zero overshoot, in both simulations and experiments. The LQR approach can be useful for the control of fast response DEAs and this would expand the potential use of the DEAs as artificial muscles in soft robotics.

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Ultra-stretchable and highly sensitive strain sensor based on gradient structure carbon nanotubes

Nanoscale ◽

10.1039/c8nr02528b ◽

2018 ◽

Vol 10 (28) ◽

pp. 13599-13606 ◽

Cited By ~ 31

Author(s):

Binghao Liang ◽

Zhiqiang Lin ◽

Wenjun Chen ◽

Zhongfu He ◽

Jing Zhong ◽

...

Keyword(s):

Carbon Nanotubes ◽

Carbon Nanotube ◽

Strain Sensor ◽

High Sensitivity ◽

Strain Sensors ◽

Sensitive Strain ◽

Gauge Factor ◽

Gradient Structure ◽

Highly Sensitive ◽

Highly Stretchable

A highly stretchable and sensitive strain sensor based on a gradient carbon nanotube was developed. The strain sensors show an unprecedented combination of both high sensitivity (gauge factor = 13.5) and ultra-stretchability (>550%).

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