Characteristics of dielectric elastomers and fabrication of dielectric elastomer actuators for artificial muscle applications

This paper appraisals state-of-the-art dielectric elastomer actuators (DEAs) and their forthcoming standpoints as soft actuators which have freshly been considered as a crucial power generation module for soft robots. DEs behave as yielding capacitors, expanding in area and attenuation in thickness when a voltage is applied. The paper initiates with the explanation of working principle of dielectric elastomer grippers. Here the operation of DEAs include both physics and mechanical properties with its characteristics, we have describe methods for modelling and its introductory application. In inclusion, the artificial muscle based on DEA concept is also formally presented. This paper also elaborates DEAs popular application such as- Soft Robotics, Robotics grippers and artificial muscles.

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Contractile and Buckling Actuators Based on Dielectric Elastomers: Devices and Applications

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.61.186 ◽

2008 ◽

Vol 61 ◽

pp. 186-191 ◽

Cited By ~ 4

Author(s):

Federico Carpi ◽

Gabriele Frediani ◽

Andrea Mannini ◽

Danilo De Rossi

Keyword(s):

Artificial Muscle ◽

Dielectric Elastomer ◽

Electroactive Polymer ◽

Dielectric Elastomers ◽

Interdigitated Electrodes ◽

Out Of Plane

Dielectric elastomer (DE) actuators are able to typically show significant electromechanical performances, which make this electroactive polymer technology particularly attractive for so-called ‘artificial muscle’ devices. This paper deals with two types of DE actuators recently developed in our lab. The first type is represented by the so-called ‘folded actuators’, based on a simple configuration suitable to easily implement linear contractile devices. The structure consists of a monolithic electroded sheet of elastomer, which is folded up and compacted; the resulting contractile actuator is functionally equivalent to a multilayer stack with interdigitated electrodes, but can be manufactured more easily. The second type of devices is represented by the so-called ‘buckling actuators’. They operate with out-of-plane unidirectional displacements of an elastomer membrane. This paper describes the structure and the properties of both these actuators, along with different examples of applications currently being developed in our lab for the biomedical, the robotic and the space fields.

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Instability in Nonlinear Oscillation of Dielectric Elastomers

Journal of Applied Mechanics ◽

10.1115/1.4030075 ◽

2015 ◽

Vol 82 (6) ◽

Cited By ~ 13

Author(s):

Jian Zhu

Keyword(s):

Nonlinear Oscillation ◽

Electromechanical Coupling ◽

Haptic Feedback ◽

Dynamic Instability ◽

Dielectric Elastomer ◽

Dielectric Elastomers ◽

Critical Amplitude ◽

Dielectric Elastomer Actuators ◽

Coupling Dynamic ◽

Static Instability

A membrane of a dielectric elastomer oscillates when subject to AC voltage. Its oscillation is nonlinear due to large deformation and nonlinear electromechanical coupling. Dynamic instability in dielectric elastomers—the oscillation with an unbounded amplitude—is investigated in this paper. The critical amplitude of AC voltage for dynamic instability varies with the frequency of AC voltage and reaches a valley when the superharmonic, harmonic, or subharmonic resonance is excited. Prestretches can improve dielectric elastomer actuators' capabilities to resist dynamic instability. The critical deformation at the onset of dynamic instability can be much larger than that at the onset of static instability. Oscillation of dielectric elastomers can be used for applications, such as vibration shakers for haptic feedback, soft loudspeakers, soft motors, and soft pumps. We hope that the current analyses can improve the understanding of dynamic behavior of dielectric elastomers and enhance their stability and reliability.

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Soft, tough, and fast polyacrylate dielectric elastomer for non-magnetic motor

Nature Communications ◽

10.1038/s41467-021-24851-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Li-Juan Yin ◽

Yu Zhao ◽

Jing Zhu ◽

Minhao Yang ◽

Huichan Zhao ◽

...

Keyword(s):

High Performance ◽

Crosslinking Agent ◽

High Energy ◽

Dielectric Elastomer ◽

High Energy Density ◽

Dielectric Elastomers ◽

Dielectric Elastomer Actuators ◽

Response Bandwidth ◽

Electrically Actuated ◽

Soft Actuators

AbstractDielectric elastomer actuators (DEAs) with large electrically-actuated strain can build light-weight and flexible non-magnetic motors. However, dielectric elastomers commonly used in the field of soft actuation suffer from high stiffness, low strength, and high driving field, severely limiting the DEA’s actuating performance. Here we design a new polyacrylate dielectric elastomer with optimized crosslinking network by rationally employing the difunctional macromolecular crosslinking agent. The proposed elastomer simultaneously possesses desirable modulus (~0.073 MPa), high toughness (elongation ~2400%), low mechanical loss (tan δm = 0.21@1 Hz, 20 °C), and satisfactory dielectric properties ($${\varepsilon }_{{{{{{\rm{r}}}}}}}$$ ε r = 5.75, tan δe = 0.0019 @1 kHz), and accordingly, large actuation strain (118% @ 70 MV m−1), high energy density (0.24 MJ m−3 @ 70 MV m−1), and rapid response (bandwidth above 100 Hz). Compared with VHBTM 4910, the non-magnetic motor made of our elastomer presents 15 times higher rotation speed. These findings offer a strategy to fabricate high-performance dielectric elastomers for soft actuators.

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Soft Freestanding Planar Artificial Muscle Based on Dielectric Elastomer Actuator

Journal of Applied Mechanics ◽

10.1115/1.4039289 ◽

2018 ◽

Vol 85 (5) ◽

Cited By ~ 7

Author(s):

Lei Qin ◽

Jiawei Cao ◽

Yucheng Tang ◽

Jian Zhu

Keyword(s):

Structural Complexity ◽

Artificial Muscle ◽

High Energy ◽

Dielectric Elastomer ◽

Tactile Feedback ◽

High Energy Density ◽

Artificial Muscles ◽

Dielectric Elastomer Actuators ◽

Electromechanical Instability ◽

Compression Springs

Dielectric elastomer actuators (DEAs) exhibit interesting muscle-like attributes including large voltage-induced deformation and high energy density, thus can function as artificial muscles for soft robots/devices. This paper focuses on soft planar DEAs, which have extensive applications such as artificial muscles for jaw movement, stretchers for cell mechanotransduction, and vibration shakers for tactile feedback, etc. Specifically, we develop a soft planar DEA, in which compression springs are employed to make the entire structure freestanding. This soft freestanding actuator can achieve both linear actuation and turning without increasing the size, weight, or structural complexity, which makes the actuator suitable for driving a soft crawling robot. Furthermore, its simple structure and homogeneous deformation allow for analytic modeling, which can be used to interpret the large voltage-induced deformation and interesting mechanics phenomenon (i.e., wrinkling and electromechanical instability). A preliminary demonstration showcases that this soft planar actuator can be employed as an artificial muscle to drive a soft crawling robot.

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