Graphical Abstract Figure
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Abstract

Dielectric elastomer actuators (DEAs) have been widely studied in soft robotics due to their muscle-like movements. Linear DEAs are typically tensioned using compression springs with positive stiffness or weights directly attached to the flexible film of the DEA. In this paper, a novel class of 2D profile linear DEAs (butterfly- and X-shaped linear DEAs) with compact structure is introduced, which, employing negative-stiffness mechanisms, can largely increase the stroke of the actuators. Then, a dynamic model of the proposed amplified-stroke linear DEAs (ASL-DEAs) is developed and used to predict the actuator stroke. The fabrication process of linear DEAs is presented. This, using compliant joints, 3D-printed links, and dielectric elastomer, allows for rapid and affordable production. The experimental validation of the butterfly- and X-shaped linear DEAs proved capable of increasing the stroke up to 32.7% and 24.0%, respectively, compared with the conventional design employing springs and constant weights. Finally, the dynamic model is validated against the experimental data of stroke amplitude and output force; errors smaller than 10.5% for a large stroke amplitude (60% of maximum stroke) and 10.5% on the output force are observed.

References

1.
Gupta
,
U.
,
Qin
,
L.
,
Wang
,
Y.
,
Godaba
,
H.
, and
Zhu
,
J.
,
2019
, “
Soft Robots Based on Dielectric Elastomer Actuators: A Review
,”
Smart Mater. Struct.
,
28
(
10
), p.
103002
.
2.
Moretti
,
G.
,
Rosset
,
S.
,
Vertechy
,
R.
,
Anderson
,
I.
, and
Fontana
,
M.
,
2020
, “
A Review of Dielectric Elastomer Generator Systems
,”
Adv. Intell. Syst.
,
2
(
10
), p.
30
.
3.
Hajiesmaili
,
E.
, and
Clarke
,
D. R.
,
2021
, “
Dielectric Elastomer Actuators
,”
J. Appl. Phys.
,
129
(
15
), p.
151102
.
4.
Guo
,
R.
,
Wang
,
X.
,
Yu
,
W.
,
Tang
,
J.
, and
Liu
,
J.
,
2018
, “
A Highly Conductive and Stretchable Wearable Liquid Metal Electronic Skin for Long-Term Conformable Health Monitoring
,”
Sci. China Technol. Sci.
,
61
(
7
), pp.
1031
1037
.
5.
Wang
,
X.
,
Guo
,
R.
,
Yuan
,
B.
,
Yao
,
Y.
,
Wang
,
F.
, and
Liu
,
J.
,
2018
, “
Ni-Doped Liquid Metal Printed Highly Stretchable and Conformable Strain Sensor for Multifunctional Human-Motion Monitoring
,”
Proceedings of the 2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC)
,
Honolulu, HI
,
July 17–21
, IEEE, pp.
3276
3279
.
6.
Mitra
,
A.
,
Xu
,
K.
,
Babu
,
S.
,
Choi
,
J. H.
, and
Lee
,
J.-B.
,
2021
, “
Liquid Metal-Based Flexible Band-Stop Frequency Selective Surface
,”
Proceedings of the 2021 IEEE 34th International Conference on Micro Electro Mechanical Systems (MEMS)
,
Virtual Conference
,
Jan. 25–29
, IEEE, pp.
953
956
.
7.
Jeong
,
J.
,
Mitra
,
A.
, and
Lee
,
J. B. J.
,
2022
, “
Atomized Liquid Metal Droplet-Enabled Enhancement of Sensing Range and Stability for Ultrasensitive Crack-Based Sensor
,”
Proceedings of the 2022 IEEE Sensors
,
Dallas, TX
,
Oct. 30–Nov. 2
, IEEE, pp.
01
04
.
8.
Gu
,
G.
,
Zou
,
J.
,
Zhao
,
R.
,
Zhao
,
X.
, and
Zhu
,
X.
,
2018
, “
Soft Wall-Climbing Robots
,”
Sci. Robot.
,
3
(
25
), p.
eaat2874
.
9.
Henke
,
E. M.
,
Schlatter
,
S.
, and
Anderson
,
I. A.
,
2017
, “
Soft Dielectric Elastomer Oscillators Driving Bioinspired Robots
,”
Soft Robot.
,
4
(
4
), pp.
353
366
.
10.
Hu
,
T. T.
,
Lu
,
X. J.
, and
Liu
,
J.
,
2023
, “
Inchworm-Like Soft Robot With Multimodal Locomotion Using an Acrylic Stick-Constrained Dielectric Elastomer Actuator
,”
Adv. Intell. Syst.
,
5
(
2
), p.
13
.
11.
Chen
,
B. C.
,
Wang
,
N. F.
,
Wang
,
R. X.
,
Zhu
,
B. L.
,
Zhang
,
X. M.
,
Sun
,
W. J.
, and
Chen
,
W.
,
2023
, “
Automatic Design of Dielectric Elastomer-Based Crawling Robots Using Shape and Topology Optimization
,”
ASME J. Mech. Rob.
,
15
(
2
), p.
021006
.
12.
Chen
,
Y.
,
Zhao
,
H.
,
Mao
,
J.
,
Chirarattananon
,
P.
,
Helbling
,
E. F.
,
Hyun
,
N. P.
,
Clarke
,
D. R.
, and
Wood
,
R. J.
,
2019
, “
Controlled Flight of a Microrobot Powered by Soft Artificial Muscles
,”
Nature
,
575
(
7782
), pp.
324
329
.
13.
Sriratanasak
,
N.
,
Axinte
,
D.
,
Dong
,
X.
,
Mohammad
,
A.
,
Russo
,
M.
, and
Raimondi
,
L.
,
2022
, “
Tasering Twin Soft Robot: A Multimodal Soft Robot Capable of Passive Flight and Wall Climbing
,”
Adv. Intell. Syst.
,
4
(
12
), p.
13
.
14.
Shintake
,
J.
,
Cacucciolo
,
V.
,
Shea
,
H.
, and
Floreano
,
D.
,
2018
, “
Soft Biomimetic Fish Robot Made of Dielectric Elastomer Actuators
,”
Soft Robot.
,
5
(
4
), pp.
466
474
.
15.
Christianson
,
C.
,
Goldberg
,
N. N.
,
Deheyn
,
D. D.
,
Cai
,
S.
, and
Tolley
,
M. T.
,
2018
, “
Translucent Soft Robots Driven by Frameless Fluid Electrode Dielectric Elastomer Actuators
,”
Sci. Robot.
,
3
(
17
), p.
eaat1893
.
16.
Araromi
,
O. A.
,
Gavrilovich
,
I.
,
Shintake
,
J.
,
Rosset
,
S.
,
Richard
,
M.
,
Gass
,
V.
, and
Shea
,
H. R.
,
2015
, “
Rollable Multisegment Dielectric Elastomer Minimum Energy Structures for a Deployable Microsatellite Gripper
,”
IEEE/ASME Trans. Mechatron.
,
20
(
1
), pp.
438
446
.
17.
Shintake
,
J.
,
Rosset
,
S.
,
Schubert
,
B.
,
Floreano
,
D.
, and
Shea
,
H.
,
2016
, “
Versatile Soft Grippers With Intrinsic Electroadhesion Based on Multifunctional Polymer Actuators
,”
Adv. Mater.
,
28
(
2
), pp.
231
238
.
18.
Atia
,
M. G. B.
,
Mohammad
,
A.
,
Gameros
,
A.
,
Axinte
,
D.
, and
Wright
,
I.
,
2022
, “
Reconfigurable Soft Robots by Building Blocks
,”
Adv. Sci.
,
9
(
33
), p.
2203217
.
19.
Gu
,
G.-Y.
,
Gupta
,
U.
,
Zhu
,
J.
,
Zhu
,
L.-M.
, and
Zhu
,
X.
,
2017
, “
Modeling of Viscoelastic Electromechanical Behavior in a Soft Dielectric Elastomer Actuator
,”
IEEE Trans. Robot.
,
33
(
5
), pp.
1263
1271
.
20.
Sheng
,
J.
,
Chen
,
H.
,
Li
,
B.
, and
Wang
,
Y.
,
2014
, “
Nonlinear Dynamic Characteristics of a Dielectric Elastomer Membrane Undergoing in-Plane Deformation
,”
Smart Mater. Struct.
,
23
(
4
), p.
045010
.
21.
Li
,
L.
,
Godaba
,
H.
,
Ren
,
H.
, and
Zhu
,
J.
,
2019
, “
Bioinspired Soft Actuators for Eyeball Motions in Humanoid Robots
,”
IEEE/ASME Trans. Mechatron.
,
24
(
1
), pp.
100
108
.
22.
Liu
,
L.
,
Zhang
,
J.
,
Luo
,
M.
,
Chen
,
H.
,
Yang
,
Z.
,
Li
,
D.
, and
Li
,
P.
,
2020
, “
A Bio-Inspired Soft-Rigid Hybrid Actuator Made of Electroactive Dielectric Elastomers
,”
Appl. Mater. Today
,
21
, p.
100814
.
23.
Kanno
,
R.
,
Caruso
,
F.
,
Takai
,
K.
,
Piskarev
,
Y.
,
Cacucciolo
,
V.
, and
Shintake
,
J.
,
2023
, “
Biodegradable Electrohydraulic Soft Actuators
,”
Adv. Intell. Syst.
,
5
(
9
), p.
2200239
.
24.
Kellaris
,
N.
,
Venkata
,
V. G.
,
Smith
,
G. M.
,
Mitchell
,
S. K.
, and
Keplinger
,
C.
,
2018
, “
Peano-HASEL Actuators: Muscle-Mimetic, Electrohydraulic Transducers That Linearly Contract on Activation
,”
Sci. Robot.
,
3
(
14
), p.
eaar3276
.
25.
Hau
,
S.
,
Bruch
,
D.
,
Rizzello
,
G.
,
Motzki
,
P.
, and
Seelecke
,
S.
,
2018
, “
Silicone Based Dielectric Elastomer Strip Actuators Coupled With Nonlinear Biasing Elements for Large Actuation Strains
,”
Smart Mater. Struct.
,
27
(
7
), p.
074003
.
26.
Loew
,
P.
,
Rizzello
,
G.
, and
Seelecke
,
S.
,
2018
, “
A Novel Biasing Mechanism for Circular Out-of-Plane Dielectric Actuators Based on Permanent Magnets
,”
Mechatronics
,
56
, pp.
48
57
.
27.
Hodgins
,
M.
, and
Seelecke
,
S.
,
2011
, “
Experimental Analysis of Biasing Elements for Dielectric Electro-Active Polymers
,”
Proceedings of the Conference on Electroactive Polymer Actuators and Devices (EAPAD) 2011
,
San Diego, CA
,
Mar. 7–10
.
28.
Hodgins
,
M.
,
York
,
A.
, and
Seelecke
,
S.
,
2013
, “
Experimental Comparison of Bias Elements for out-of-Plane DEAP Actuator System
,”
Smart Mater. Struct.
,
22
(
9
), p.
9
.
29.
Wang
,
N. F.
,
Cui
,
C. Y.
,
Chen
,
B. C.
,
Guo
,
H.
, and
Zhang
,
X. M.
,
2019
, “
Design of Translational and Rotational Bistable Actuators Based on Dielectric Elastomer
,”
ASME J. Mech. Rob.
,
11
(
4
), p.
041011
.
30.
Croce
,
S.
,
Neu
,
J.
,
Hubertus
,
J.
,
Seelecke
,
S.
,
Schultes
,
G.
, and
Rizzello
,
G.
,
2021
, “
Model-Based Design Optimization of Soft Polymeric Domes Used as Nonlinear Biasing Systems for Dielectric Elastomer Actuators
,”
Actuators
,
10
(
9
), p.
25
.
31.
Neu
,
J.
,
Hubertus
,
J.
,
Croce
,
S.
,
Schultes
,
G.
,
Seelecke
,
S.
, and
Rizzello
,
G.
,
2021
, “
Fully Polymeric Domes as High-Stroke Biasing System for Soft Dielectric Elastomer Actuators
,”
Front. Robot. AI
,
8
(
10
), p.
695918
.
32.
Berselli
,
G.
,
Vertechy
,
R.
,
Vassura
,
G.
,
Castelli
,
V. P.
, and
ASME
,
2009
, “
Design of a Single-Acting Constant-Force Actuator Based on Dielectric Elastomers
,”
Proceedings of the Detc 2008: 32nd Annual Mechanisms and Robotics Conference, San Diego, CA, Aug. 30–Sept. 2, Vol. 2, Parts A & B
, pp.
313
321
.
33.
Bruch
,
D.
,
Willian
,
T. P.
,
Schafer
,
H. C.
, and
Motzki
,
P.
,
2022
, “
Performance-Optimized Dielectric Elastomer Actuator System With Scalable Scissor Linkage Transmission
,”
Actuators
,
11
(
6
), p.
19
.
34.
He
,
T. H.
,
Cui
,
L. L.
,
Chen
,
C.
, and
Suo
,
Z. G.
,
2010
, “
Nonlinear Deformation Analysis of a Dielectric Elastomer Membrane-Spring System
,”
Smart Mater. Struct.
,
19
(
8
), p.
085017
.
35.
Rosset
,
S.
,
Araromi
,
O. A.
,
Shintake
,
J.
, and
Shea
,
H. R.
,
2014
, “
Model and Design of Dielectric Elastomer Minimum Energy Structures
,”
Smart Mater. Struct.
,
23
(
8
), p.
12
.
36.
Zou
,
J.
, and
Gu
,
G.
,
2019
, “
Feedforward Control of the Rate-Dependent Viscoelastic Hysteresis Nonlinearity in Dielectric Elastomer Actuators
,”
IEEE Robot. Autom. Lett.
,
4
(
3
), pp.
2340
2347
.
37.
Sarban
,
R.
,
Lassen
,
B.
, and
Willatzen
,
M.
,
2012
, “
Dynamic Electromechanical Modeling of Dielectric Elastomer Actuators With Metallic Electrodes
,”
IEEE/ASME Trans. Mechatron.
,
17
(
5
), pp.
960
967
.
38.
Zou
,
J.
, and
Gu
,
G.
,
2019
, “
Dynamic Modeling of Dielectric Elastomer Actuators With a Minimum Energy Structure
,”
Smart Mater. Struct.
,
28
(
8
), p.
085039
.
39.
Meng
,
L. D.
,
Kang
,
R. J.
,
Gan
,
D. M.
,
Chen
,
G. M.
,
Chen
,
L. S.
,
Branson
,
D. T.
, and
Dai
,
J. S.
,
2020
, “
A Mechanically Intelligent Crawling Robot Driven by Shape Memory Alloy and Compliant Bistable Mechanism
,”
ASME J. Mech. Rob.
,
12
(
6
), p.
061005
.
40.
Medina
,
H.
, and
Farmer
,
C. W.
,
2020
, “
Improved Model for Conical Dielectric Elastomer Actuators With Fewer Electrical Connections
,”
ASME J. Mech. Rob.
,
12
(
3
), p.
10
.
41.
Correa
,
D. M.
,
Seepersad
,
C. C.
, and
Haberman
,
M. R.
,
2015
, “
Mechanical Design of Negative Stiffness Honeycomb Materials
,”
Integr. Mater. Manuf. Innov.
,
4
(
1
), pp.
165
175
.
42.
Lakes
,
R. S.
,
Lee
,
T.
,
Bersie
,
A.
, and
Wang
,
Y. C.
,
2001
, “
Extreme Damping in Composite Materials With Negative-Stiffness Inclusions
,”
Nature
,
410
(
6828
), pp.
565
567
.
43.
Izard
,
A. G.
,
Alfonso
,
R. F.
,
McKnight
,
G.
, and
Valdevit
,
L.
,
2017
, “
Optimal Design of a Cellular Material Encompassing Negative Stiffness Elements for Unique Combinations of Stiffness and Elastic Hysteresis
,”
Mater. Des.
,
135
(
5
), pp.
37
50
.
44.
Howell
,
L. L.
,
Compliant Mechanisms
,
Springer
,
London
, pp.
189
216
.
45.
Kollosche
,
M.
,
Kofod
,
G.
,
Suo
,
Z.
, and
Zhu
,
J.
,
2015
, “
Temporal Evolution and Instability in a Viscoelastic Dielectric Elastomer
,”
J. Mech. Phys. Solids
,
76
, pp.
47
64
.
46.
Rus
,
D.
, and
Tolley
,
M. T.
,
2018
, “
Design, Fabrication and Control of Origami Robots
,”
Nat. Rev. Mater
,
3
(
6
), pp.
101
112
.
47.
Tan
,
X. J.
,
Wang
,
B.
,
Zhu
,
S. W.
,
Chen
,
S.
,
Yao
,
K. L.
,
Xu
,
P. F.
,
Wu
,
L. Z.
, and
Sun
,
Y. G.
,
2020
, “
Novel Multidirectional Negative Stiffness Mechanical Metamaterials
,”
Smart Mater. Struct.
,
29
(
1
), p.
015037
.
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