Propulsive capability of manta rays' flapping pectoral fins has inspired many to incorporate these fins as propulsive mechanisms for autonomous underwater vehicles. In particular, geometrical factors such as sweep angle have been postulated as being influential to these fins' propulsive capability, specifically their thrust generation. Although effects of sweep angle on static/flapping wings of aircrafts/drones have been widely studied, little has been done for underwater conditions. Furthermore, the findings from air studies may not be relatable to the underwater studies on pectoral fins because of the different Reynolds number (compared to the flapping wings) and force generation mechanism (compared to the static wings). This paper aims to establish a relationship between the sweep angle and thrust generation. An experiment was conducted to measure the thrust generated by 40 fins in a water channel under freestream and still water conditions for chord Reynolds number between 2.2 × 104 and 8.2 × 104. The fins were of five different sweep angles (0 deg, 10 deg, 20 deg, 30 deg, and 40 deg) that were incorporated into eight base designs of different flexibility characteristics. The results showed that the sweep angle (within the range considered) may have no significant influence on these fins' thrust generation, implying no significant effects on thrust under uniform flow condition and on the maximum possible thrust under still water. Overall, it can be concluded that sweep angle may not be a determinant of thrust generation for flapping pectoral fins. This knowledge can ease the decision-making process of design of robots propeled by these fins.

References

References
1.
Lauder
,
G. V.
, and
Madden
,
P. G.
,
2006
, “
Learning From Fish: Kinematics and Experimental Hydrodynamics for Roboticists
,”
Int. J. Autom. Comput.
,
3
(
4
), pp.
325
335
.
2.
Clark
,
R. P.
, and
Smits
,
A. J.
,
2006
, “
Thrust Production and Wake Structure of a Batoid-Inspired Oscillating Fin
,”
J. Fluid Mech.
,
562
, pp.
415
429
.
3.
Tangorra
,
J. L.
,
Davidson
,
S. N.
,
Hunter
,
I. W.
,
Madden
,
P. G.
,
Lauder
,
G. V.
,
Dong
,
H.
,
Bozkurttas
,
M.
, and
Mittal
,
R.
,
2007
, “
The Development of a Biologically Inspired Propulsor for Unmanned Underwater Vehicles
,”
IEEE J. Oceanic Eng.
,
32
(
3
), pp.
533
550
.
4.
Braun
,
C. D.
,
Skomal
,
G. B.
,
Thorrold
,
S. R.
, and
Berumen
,
M. L.
,
2014
, “
Diving Behavior of the Reef Manta Ray Links Coral Reefs With Adjacent Deep Pelagic Habitats
,”
PLoS One
,
9
(
2
), p.
e88170
.
5.
Dewey
,
P. A.
,
Carriou
,
A.
, and
Smits
,
A. J.
,
2012
, “
On the Relationship Between Efficiency and Wake Structure of a Batoid-Inspired Oscillating Fin
,”
J. Fluid Mech.
,
691
, pp.
245
266
.
6.
Cai
,
Y.
,
Bi
,
S.
,
Zhang
,
L.
, and
Gao
,
J.
,
2009
, “
Design of a Robotic Fish Propelled by Oscillating Flexible Pectoral Foils
,”
IEEE/RSJ
International Conference on Intelligent Robots and Systems
, St. Louis, MO, Oct. 10–15, pp.
2138
2142
.
7.
Griffiths
,
G.
,
2002
,
Technology and Applications of Autonomous Underwater Vehicles
, Vol.
2
,
CRC Press
, London.
8.
Moored
,
K. W.
,
Dewey
,
P. A.
,
Leftwich
,
M. C.
,
Bart-Smith
,
H.
, and
Smits
,
A. J.
,
2011
, “
Bioinspired Propulsion Mechanisms Based on Manta Ray Locomotion
,”
Mar. Technol. Soc. J.
,
45
(
4
), pp.
110
118
.
9.
Rosenberger
,
L. J.
,
2001
, “
Pectoral Fin Locomotion in Batoid Fishes: Undulation Versus Oscillation
,”
J. Exp. Biol.
,
204
(
2
), pp.
379
394
.http://jeb.biologists.org/content/204/2/379
10.
Wang
,
Z. J.
,
2000
, “
Vortex Shedding and Frequency Selection in Flapping Flight
,”
J. Fluid Mech.
,
410
, pp.
323
341
.
11.
Glauert
,
H.
,
1929
,
The Force and Moment on an Oscillating Aerofoil
,
HM Stationery Office
, Richmond, UK.
12.
Kikuchi
,
K.
,
Uehara
,
Y.
,
Kubota
,
Y.
, and
Mochizuki
,
O.
,
2014
, “
Morphological Considerations of Fish Fin Shape on Thrust Generation
,”
J. Appl. Fluid Mech.
,
7
(
4
), pp.
625
632
.http://jafmonline.net/web/guest/home?p_p_id=JournalArchive_WAR_JournalArchive_INSTANCE_nvhn&p_p_action=0&p_p_state=maximized&p_p_mode=view&_JournalArchive_WAR_JournalArchive_INSTANCE_nvhn_form_page=main_form&selectedVolumeId=66&selectedIssueId=219
13.
Alben
,
S.
,
Witt
,
C.
,
Baker
,
T. V.
,
Anderson
,
E.
, and
Lauder
,
G. V.
,
2012
, “
Dynamics of Freely Swimming Flexible Foils
,”
Phys. Fluids
,
24
(
5
), p.
051901
.
14.
Lowson
,
M.
, and
Riley
,
A.
,
1995
, “
Vortex Breakdown Control by Delta Wing Geometry
,”
J. Aircr.
,
32
(
4
), pp.
832
838
.
15.
Orlowski
,
C. T.
, and
Girard
,
A. R.
,
2012
, “
Dynamics, Stability, and Control Analyses of Flapping Wing Micro-Air Vehicles
,”
Prog. Aerosp. Sci.
,
51
, pp.
18
30
.
16.
Yaniktepe
,
B.
, and
Rockwell
,
D.
,
2004
, “
Flow Structure on a Delta Wing of Low Sweep Angle
,”
AIAA J.
,
42
(
3
), pp.
513
523
.
17.
Stephen
,
E. J.
, and
Sopirak
,
D. A.
,
1996
, “
Effects of Leading-Edge Sweep Angle on Nonzero Trimmed Roll Angles
,”
J. Aircr.
,
33
(
4
), pp.
825
828
.
18.
Lentink
,
D.
,
Müller
,
U.
,
Stamhuis
,
E.
,
De Kat
,
R.
,
Van Gestel
,
W.
,
Veldhuis
,
L.
,
Henningsson
,
P.
,
Hedenström
,
A.
,
Videler
,
J. J.
, and
Van Leeuwen
,
J. L.
,
2007
, “
How Swifts Control Their Glide Performance With Morphing Wings
,”
Nature
,
446
(
7139
), pp.
1082
1085
.
19.
Anderson
,
J. M.
,
Streitlien
,
K.
,
Barrett
,
D. S.
, and
Triantafyllou
,
M. S.
,
1998
, “
Oscillating Foils of High Propulsive Efficiency
,”
J. Fluid Mech.
,
360
, pp.
41
72
.
20.
Toomey
,
J.
, and
Eldredge
,
J. D.
,
2006
, “
Numerical and Experimental Investigation of the Role of Flexibility in Flapping Wing Flight
,”
AIAA
Paper No. AIAA-2006-3211.
21.
Arastehfar
,
S.
,
Chew
,
C-M.
,
Jalalian
,
A.
, and
Yeo
,
K. S.
,
2018
, “
Study of Effects of Constraining Root Chord Movement on Thrust Generation of Oscillatory Pectoral Fins
,”
IEEE International Conference on Robotics and Biomimetics (ROBIO)
,
Kuala Lumpur, Malaysia
,
Dec. 12–15
, pp.
1
6
.
22.
Festo, 2016, “
Festo Aqua Ray
,” Festo AG & Co.KG, Esslingen, Germany, accessed Apr. 1, 2016, https://www.festo.com/PDF_Flip/corp/Festo_Aqua_ray/en/files/assets/basic-html/page-1.html
23.
Gao
,
J.
,
Bi
,
S.
,
Li
,
J.
, and
Cai
,
Y.
,
2011
, “
Design and Hydrodynamic Experiments on Robotic Fish With Oscillation Pectoral Fins
,”
J. Beijing Univ. Aeronaut. Astronaut.
,
37
(
3
), pp.
344
350
.http://bhxb.buaa.edu.cn/EN/volumn/current.shtml
24.
Yang
,
S.-B.
,
Qiu
,
J.
, and
Han
,
X.-Y.
,
2009
, “
Kinematics Modeling and Experiments of Pectoral Oscillation Propulsion Robotic Fish
,”
J. Bionic Eng.
,
6
(
2
), pp.
174
179
.
25.
Chew
,
C. M.
,
Arastehfar
,
S.
,
Gunawan
,
G.
, and
Yeo
,
K. S.
,
2017
, “
Study of Sweep Angle Effect on the Thrust Generation of Oscillatory Pectoral Fins
,”
IEEE/RSJ International Conference on Intelligent Robots and Systems
(
IROS
), Vancouver, BC, Canada, Sept. 24–28.
26.
Moored
,
K. W.
,
Smith
,
W.
,
Hester
,
J.
,
Chang
,
W.
, and
Bart-Smith
,
H.
, “
Investigating the Thrust Production of a Myliobatoid-Inspired Oscillating Wing
,”
Adv. Sci. Technol.
,
58
, pp.
25
30
.
27.
Arastehfar
,
S.
,
Gunawan
,
G.
,
Yeo
,
K. S.
, and
Chew
,
C. M.
,
2017
, “
Effects of Pectoral Fins' Spanwise Flexibility on Forward Thrust Generation
,”
IEEE International Conference on Robotics and Biomimetics
(
ROBIO
),
Macau, China
,
Dec. 5–8
.
28.
Chen
,
Z.
,
Um
,
T. I.
,
Zhu
,
J.
, and
Bart-Smith
,
H.
,
2011
, “
Bio-Inspired Robotic Cownose Ray Propelled by Electroactive Polymer Pectoral Fin
,”
ASME
Paper No. IMECE2011-64174.
29.
Fish
,
F. E.
,
Schreiber
,
C. M.
,
Moored
,
K. W.
,
Liu
,
G.
,
Dong
,
H.
, and
Bart-Smith
,
H.
,
2016
, “
Hydrodynamic Performance of Aquatic Flapping: Efficiency of Underwater Flight in the Manta
,”
Aerospace
,
3
(
3
), p.
20
.
30.
Russo
,
R.
,
Blemker
,
S.
,
Fish
,
F.
, and
Bart-Smith
,
H.
,
2015
, “
Biomechanical Model of Batoid (skates and Rays) Pectoral Fins Predicts the Influence of Skeletal Structure on Fin Kinematics: Implications for Bio-Inspired Design
,”
Bioinspiration Biomimetics
,
10
(
4
), p.
046002
.
31.
Fish
,
F. E.
, and
Nicastro
,
A. J.
,
2003
, “
Aquatic Turning Performance by the Whirligig Beetle: Constraints on Maneuverability by a Rigid Biological System
,”
J. Exp. Biol.
,
206
(
10
), pp.
1649
1656
.
32.
Parson
,
J. M.
,
Fish
,
F. E.
, and
Nicastro
,
A. J.
,
2011
, “
Turning Performance of Batoids: Limitations of a Rigid Body
,”
J. Exp. Mar. Biol. Ecol.
,
402
(
1–2
), pp.
12
18
.
33.
ATI, 2016, “
ATI Industrial Automation
,” ATI Industrial Automation, Apex, NC, accessed Apr. 1, 2016, https://www.ati-ia.com/Products/ft/sensors.aspx
34.
Hover
,
F. S.
,
Haugsdal
,
Ø.
, and
Triantafyllou
,
M. S.
,
2004
, “
Effect of Angle of Attack Profiles in Flapping Foil Propulsion
,”
J. Fluids Struct.
,
19
(
1
), pp.
37
47
.
35.
Thaweewat
,
N.
,
Phoemsapthawee
,
S.
, and
Juntasaro
,
V.
,
2018
, “
Semi-Active Flapping Foil for Marine Propulsion
,”
Ocean Eng.
,
147
, pp.
556
564
.
36.
Young
,
J.
,
Lai
,
J. C. S.
, and
Platzer
,
M. F.
,
2014
, “
A Review of Progress and Challenges in Flapping Foil Power Generation
,”
Prog. Aerosp. Sci.
,
67
, pp.
2
28
.
37.
Li
,
W.
, and
Lauder
,
G.
,
2013
, “
Understanding Undulatory Locomotion in Fishes Using an Inertia-Compensated Flapping Foil Robotic Device
,”
Bioinspir. Biomim.
,
8
(
4
), p.
046013
.
38.
Lucas
,
K. N.
,
Johnson
,
N.
,
Beaulieu
,
W. T.
,
Cathcart
,
E.
,
Tirrell
,
G.
,
Colin
,
S. P.
,
Gemmell
,
B. J.
,
Dabiri
,
J. O.
, and
Costello
,
J. H.
,
2014
, “
Bending Rules for Animal Propulsion
,”
Nat. Commun.
,
5
, p.
3293
.
39.
Ketchen
,
D. J.
, and
Shook
,
C. L.
,
1996
, “
The Application of Cluster Analysis in Strategic Management Research: An Analysis and Critique
,”
Strategic Manage. J.
,
17
(
6
), pp.
441
458
.
You do not currently have access to this content.