Abstract

We report a surface treatment for an elastomeric dry adhesive that improves adhesion, especially on surfaces with microscopic roughness. The process involves coating wedge-shaped polydimethylsiloxane (PDMS) features of the adhesive with a 50 nm coating of poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). As compared to the uncoated adhesive, performance is 1.25× better on smooth surfaces like glass, with a maximum shear stress of 70 kPa in shear and 25 kPa in normal adhesion under controlled loading conditions. On slightly rough surfaces such as paper and panels painted with flat paint, it provides between 2.5× and over 12× greater shear stress than the uncoated adhesive. Moreover, the coating, being much stiffer than the underlying wedges, does not increase the tendency to become dirty and does not tend to self-stick, or clump. Durability tests show that the performance remains substantially unchanged for 80,000 attachment/loading/detachment cycles. We describe the coating process, present the test results, and discuss the reasons for the enhanced performance on a variety of materials.

References

References
1.
Kim
,
S.
,
Spenko
,
M.
,
Trujillo
,
S.
,
Heyneman
,
B.
,
Santos
,
D.
, and
Cutkosky
,
M. R.
,
2008
, “
Smooth Vertical Surface Climbing With Directional Adhesion
,”
IEEE Trans. Robot.
,
24
(
1
), pp.
65
74
.10.1109/TRO.2007.909786
2.
Murphy
,
M. P.
,
Kute
,
C.
,
Mengüç
,
Y.
, and
Sitti
,
M.
,
2011
, “
Waalbot II: Adhesion Recovery and Improved Performance of a Climbing Robot Using Fibrillar Adhesives
,”
Int. J. Rob. Res.
,
30
(
1
), pp.
118
133
.10.1177/0278364910382862
3.
Kalouche
,
S.
,
Wiltsie
,
N.
,
Su
,
H.-J.
, and
Parness
,
A.
,
2014
, “
Inchworm Style Gecko Adhesive Climbing Robot
,”
IEEE/RSJ International Conference on Intelligent Robots and Systems
,
Chicago, IL
, Sept. 14–18, pp.
2319
2324
.10.1109/IROS.2014.6942876
4.
Jiang
,
H.
,
Hawkes
,
E. W.
,
Fuller
,
C.
,
Estrada
,
M. A.
,
Suresh
,
S. A.
,
Abcouwer
,
N.
,
Han
,
A. K.
,
Wang
,
S.
,
Ploch
,
C. J.
,
Parness
,
A.
, and
Cutkosky
,
M. R.
,
2017
, “
A Robotic Device Using Gecko-Inspired Adhesives Can Grasp and Manipulate Large Objects in Microgravity
,”
Sci. Rob.
,
2
(
7
), p.
eaan4545
.10.1126/scirobotics.aan4545
5.
Hawkes
,
E. W.
,
Jiang
,
H.
,
Christensen
,
D. L.
,
Han
,
A. K.
, and
Cutkosky
,
M. R.
,
2018
, “
Grasping Without Squeezing: Design and Modeling of Shear-Activated Grippers
,”
IEEE Trans. Robot.
,
34
(
2
), pp.
303
316
.10.1109/TRO.2017.2776312
6.
Roberge
,
J.-P.
,
Ruotolo
,
W.
,
Duchaine
,
V.
, and
Cutkosky
,
M.
,
2018
, “
Improving Industrial Grippers With Adhesion-Controlled Friction
,”
IEEE Rob. Autom. Lett.
,
3
(
2
), pp.
1041
1048
.10.1109/LRA.2018.2794618
7.
Glick
,
P.
,
Suresh
,
S. A.
,
Ruffatto
,
D.
,
Cutkosky
,
M.
,
Tolley
,
M. T.
, and
Parness
,
A.
,
2018
, “
A Soft Robotic Gripper With Gecko-Inspired Adhesive
,”
IEEE Rob. Autom. Lett.
,
3
(
2
), pp.
903
910
.10.1109/LRA.2018.2792688
8.
Boesel
,
L. F.
,
Greiner
,
C.
,
Arzt
,
E.
, and
Del Campo
,
A.
,
2010
, “
Gecko-Inspired Surfaces: A Path to Strong and Reversible Dry Adhesives
,”
Adv. Mater.
,
22
(
19
), pp.
2125
2137
.10.1002/adma.200903200
9.
Kamperman
,
M.
,
Kroner
,
E.
,
del Campo
,
A.
,
McMeeking
,
R. M.
, and
Arzt
,
E.
,
2010
, “
Functional Adhesive Surfaces With “Gecko” Effect: The Concept of Contact Splitting
,”
Adv. Eng. Mater.
,
12
(
5
), pp.
335
348
.10.1002/adem.201000104
10.
Sameoto
,
D.
, and
Menon
,
C.
,
2010
, “
Recent Advances in the Fabrication and Adhesion Testing of Biomimetic Dry Adhesives
,”
Smart Mater. Struct.
,
19
(
10
), p.
103001
.10.1088/0964-1726/19/10/103001
11.
Kwak
,
M. K.
,
Pang
,
C.
,
Jeong
,
H.-E.
,
Kim
,
H.-N.
,
Yoon
,
H.
,
Jung
,
H.-S.
, and
Suh
,
K.-Y.
,
2011
, “
Towards the Next Level of Bioinspired Dry Adhesives: New Designs and Applications
,”
Adv. Funct. Mater.
,
21
(
19
), pp.
3606
3616
.10.1002/adfm.201100982
12.
Zhou
,
M.
,
Pesika
,
N.
,
Zeng
,
H.
,
Tian
,
Y.
, and
Israelachvili
,
J.
,
2013
, “
Recent Advances in Gecko Adhesion and Friction Mechanisms and Development of Gecko-Inspired Dry Adhesive Surfaces
,”
Friction
,
1
(
2
), pp.
114
129
.10.1007/s40544-013-0011-5
13.
Favi
,
P. M.
,
Yi
,
S.
,
Lenaghan
,
S. C.
,
Xia
,
L.
, and
Zhang
,
M.
,
2014
, “
Inspiration From the Natural World: From Bio-Adhesives to Bio-Inspired Adhesives
,”
J. Adhes. Sci. Technol.
,
28
(
3–4
), pp.
290
319
.10.1080/01694243.2012.691809
14.
Sameoto
,
D.
,
2017
, “
Manufacturing Approaches and Applications for Bioinspired Dry Adhesives
,”
Bio-Inspired Structured Adhesives
,
Springer
,
New York
, pp.
221
244
.
15.
Huber
,
G.
,
Gorb
,
S. N.
,
Hosoda
,
N.
,
Spolenak
,
R.
, and
Arzt
,
E.
,
2007
, “
Influence of Surface Roughness on Gecko Adhesion
,”
Acta Biomaterialia
,
3
(
4
), pp.
607
610
.10.1016/j.actbio.2007.01.007
16.
Gillies
,
A. G.
,
Henry
,
A.
,
Lin
,
H.
,
Ren
,
A.
,
Shiuan
,
K.
,
Fearing
,
R. S.
, and
Full
,
R. J.
,
2014
, “
Gecko Toe and Lamellar Shear Adhesion on Macroscopic, Engineered Rough Surfaces
,”
J. Exp. Biol.
,
217
(
2
), pp.
283
289
.10.1242/jeb.092015
17.
Niewiarowski
,
P. H.
,
Stark
,
A. Y.
, and
Dhinojwala
,
A.
,
2016
, “
Sticking to the Story: Outstanding Challenges in Gecko-Inspired Adhesives
,”
J. Exp. Biol.
,
219
(
7
), pp.
912
919
.10.1242/jeb.080085
18.
Yu
,
J.
,
Chary
,
S.
,
Das
,
S.
,
Tamelier
,
J.
,
Turner
,
K. L.
, and
Israelachvili
,
J. N.
,
2012
, “
Friction and Adhesion of Gecko-Inspired Pdms Flaps on Rough Surfaces
,”
Langmuir
,
28
(
31
), pp.
11527
11534
.10.1021/la301783q
19.
Kim
,
S.
, and
Sitti
,
M.
,
2006
, “
Biologically Inspired Polymer Microfibers With Spatulate Tips as Repeatable Fibrillar Adhesives
,”
Appl. Phys. Lett.
,
89
(
26
), p.
261911
.10.1063/1.2424442
20.
Murphy
,
M. P.
,
Aksak
,
B.
, and
Sitti
,
M.
,
2008
, “
Gecko-Inspired Directional and Controllable Adhesion
,”
Small
,
5
(
2
), pp.
170
175
.10.1002/smll.200801161
21.
Glass
,
P.
,
Chung
,
H.
,
Washburn
,
N. R.
, and
Sitti
,
M.
,
2009
, “
Enhanced Reversible Adhesion of Dopamine Methacrylamide-Coated Elastomer Microfibrillar Structures Under Wet Conditions
,”
Langmuir
,
25
(
12
), pp.
6607
6612
.10.1021/la9009114
22.
Sitti
,
M.
,
Cusick
,
B.
,
Aksak
,
B.
,
Nese
,
A.
,
Lee
,
H-I.
,
Dong
,
H.
,
Kowalewski
,
T.
, and
Matyjaszewski
,
K.
,
2009
, “
Dangling Chain Elastomers as Repeatable Fibrillar Adhesives
,”
ACS Appl. Mater. Interfaces
,
1
(
10
), pp.
2277
2287
.10.1021/am9004368
23.
Day
,
P.
,
Eason
,
E. V.
,
Esparza
,
N.
,
Christensen
,
D.
, and
Cutkosky
,
M.
,
2013
, “
Microwedge Machining for the Manufacture of Directional Dry Adhesives
,”
ASME J Micro Nano-Manuf.
,
1
(
1
), p.
011001
.10.1115/1.4023161
24.
Cheung
,
E.
, and
Sitti
,
M.
,
2008
, “
Adhesion of Biologically Inspired Oil-Coated Polymer Micropillars
,”
J. Adhes. Sci. Technol.
,
22
(
5–6
), pp.
569
589
.10.1163/156856108X295545
25.
Cheung
,
E.
, and
Sitti
,
M.
,
2011
, “
Enhancing Adhesion of Biologically Inspired Polymer Microfibers With a Viscous Oil Coating
,”
J. Adhes.
,
87
(
6
), pp.
547
557
.10.1080/00218464.2011.583582
26.
Suresh
,
S.
,
Christensen
,
D.
,
Hawkes
,
E.
, and
Cutkosky
,
M.
,
2015
, “
Surface and Shape Deposition Manufacturing for the Fabrication of a Curved Surface Gripper
,”
ASME J. Mech. Robot.
,
7
(
2
), p.
021005
.10.1115/1.4029492
27.
Kerst
,
C.
,
Suresh
,
S. A.
, and
Cutkosky
,
M. R.
,
2020
, “
Creating Metal Molds for Directional Gecko-Inspired Adhesives
,”
ASME J. Micro Nano-Manuf.
,
8
(
1
), p.
011004
.10.1115/1.4045764
28.
Soto
,
D.
,
Hill
,
G.
,
Parness
,
A.
,
Esparza
,
N.
,
Cutkosky
,
M.
, and
Kenny
,
T.
,
2010
, “
Effect of Fibril Shape on Adhesive Properties
,”
Appl. Phys. Lett.
,
97
(
5
), p.
053701
.10.1063/1.3464553
29.
Israelachvili
,
J. N.
,
2015
,
Intermolecular and Surface Forces
, 2nd ed.,
Academic Press
,
Cambridge, MA
.
30.
Fan
,
X.
,
Nie
,
W.
,
Tsai
,
H.
,
Wang
,
N.
,
Huang
,
H.
,
Cheng
,
Y.
,
Wen
,
R.
,
Ma
,
L.
,
Yan
,
F.
, and
Xia
,
Y.
,
2019
, “
PEDOT: PSS for Flexible and Stretchable Electronics: Modifications, Strategies, and Applications
,”
Adv. Sci.
,
6
(
19
), p.
1900813
.10.1002/advs.201900813
31.
Sarrazin
,
B.
,
Brossard
,
R.
,
Guenoun
,
P.
, and
Malloggi
,
F.
,
2016
, “
Investigation of PDMS Based BI-Layer Elasticity Via Interpretation of Apparent Young's Modulus
,”
Soft Matter
,
12
(
7
), pp.
2200
2207
.10.1039/C5SM02133B
32.
Eason
,
E.
,
2015
, “
Analysis and Measurement of Stress Distributions in Gecko Toes and Synthetic Adhesives
,” Ph.D. thesis,
Stanford University
,
Stanford, CA
.
33.
Lipomi
,
D. J.
,
Lee
,
J. A.
,
Vosgueritchian
,
M.
,
Tee
,
B. C.-K.
,
Bolander
,
J. A.
, and
Bao
,
Z.
,
2012
, “
Electronic Properties of Transparent Conductive Films of PEDOT: PSS on Stretchable Substrates
,”
Chem. Mater.
,
24
(
2
), pp.
373
382
.10.1021/cm203216m
34.
Lang
,
U.
,
Naujoks
,
N.
, and
Dual
,
J.
,
2009
, “
Mechanical Characterization of PEDOT: PSS Thin Films
,”
Synth. Met.
,
159
(
5–6
), pp.
473
479
.10.1016/j.synthmet.2008.11.005
35.
Zhu
,
Z.
,
Yang
,
G.
,
Li
,
R.
, and
Pan
,
T.
,
2017
, “
Photopatternable Pedot: Pss/Peg Hybrid Thin Film With Moisture Stability and Sensitivity
,”
Microsyst. Nanoeng.
,
3
(
1
), pp.
1
9
.10.1038/micronano.2017.4
36.
Autumn
,
K.
,
Dittmore
,
A.
,
Santos
,
D.
,
Spenko
,
M.
, and
Cutkosky
,
M.
,
2006
, “
Frictional Adhesion: A New Angle on Gecko Attachment
,”
J. Exp. Biol.
,
209
(
18
), pp.
3569
3579
.10.1242/jeb.02486
37.
Parness
,
A.
,
Soto
,
D.
,
Esparza
,
N.
,
Gravish
,
N.
,
Wilkinson
,
M.
,
Autumn
,
K.
, and
Cutkosky
,
M.
,
2009
, “
A Microfabricated Wedge-Shaped Adhesive Array Displaying Gecko-Like Dynamic Adhesion, Directionality and Long Lifetime
,”
J. R. Soc. Interface
,
6
(
41
), pp.
1223
1232
.10.1098/rsif.2009.0048
38.
Autumn
,
K.
, and
Puthoff
,
J.
,
2016
, “
Properties, Principles, and Parameters of the Gecko Adhesive System
,”
Biological Adhesives
,
A.
Smith
ed.,
Springer
,
New York
, pp.
245
280
.
39.
Poon
,
C. Y.
, and
Bhushan
,
B.
,
1995
, “
Comparison of Surface Roughness Measurements by Stylus Profiler, AFM and Non-Contact Optical Profiler
,”
Wear
,
190
(
1
), pp.
76
88
.10.1016/0043-1648(95)06697-7
40.
Bhushan
,
B.
,
2000
, “
Surface Roughness Analysis and Measurement Techniques
,”
Modern Tribology Handbook, Two Volume Set
,
CRC Press
,
Boca Raton, FL
, pp.
79
150
.
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