Research Papers

A Relationship Between Sweep Angle of Flapping Pectoral Fins and Thrust Generation

[+] Author and Article Information
Soheil Arastehfar

School of Engineering,
Deakin University,
Waurn Ponds 3216, VIC, Australia;
Department of Mechanical Engineering,
National University of Singapore,
Singapore 117575
e-mail: soheil.arastehfar@deakin.edu.au

Chee-Meng Chew

Department of Mechanical Engineering,
National University of Singapore,
Singapore 117575
e-mail: chewcm@nus.edu.sg

Athena Jalalian

Department of Mechanical Engineering,
National University of Singapore,
Singapore 117575
e-mail: athena@nus.edu.sg

Gunawan Gunawan

Department of Mechanical Engineering,
National University of Singapore,
Singapore 117575
e-mail: mpegu@nus.edu.sg

Khoon Seng Yeo

Department of Mechanical Engineering,
National University of Singapore,
Singapore 117575
e-mail: mpeyeoks@nus.edu.sg

1Corresponding author.

Contributed by the Mechanisms and Robotics Committee of ASME for publication in the JOURNAL OF MECHANISMS AND ROBOTICS. Manuscript received April 25, 2018; final manuscript received October 4, 2018; published online December 10, 2018. Assoc. Editor: Robert J. Wood.

J. Mechanisms Robotics 11(1), 011014 (Dec 10, 2018) (9 pages) Paper No: JMR-18-1118; doi: 10.1115/1.4041697 History: Received April 25, 2018; Revised October 04, 2018

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.

Copyright © 2019 by ASME
Your Session has timed out. Please sign back in to continue.


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. [CrossRef]
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. [CrossRef] [PubMed]
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. [CrossRef]
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. [CrossRef] [PubMed]
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. [CrossRef]
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.
Griffiths, G. , 2002, Technology and Applications of Autonomous Underwater Vehicles, Vol. 2, CRC Press, London.
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. [CrossRef]
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 [PubMed]
Wang, Z. J. , 2000, “ Vortex Shedding and Frequency Selection in Flapping Flight,” J. Fluid Mech., 410, pp. 323–341. [CrossRef]
Glauert, H. , 1929, The Force and Moment on an Oscillating Aerofoil, HM Stationery Office, Richmond, UK.
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
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. [CrossRef]
Lowson, M. , and Riley, A. , 1995, “ Vortex Breakdown Control by Delta Wing Geometry,” J. Aircr., 32(4), pp. 832–838. [CrossRef]
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. [CrossRef]
Yaniktepe, B. , and Rockwell, D. , 2004, “ Flow Structure on a Delta Wing of Low Sweep Angle,” AIAA J., 42(3), pp. 513–523. [CrossRef]
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. [CrossRef]
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. [CrossRef] [PubMed]
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. [CrossRef]
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.
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.
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
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
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. [CrossRef]
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.
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. [CrossRef]
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.
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.
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. [CrossRef]
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. [CrossRef] [PubMed]
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. [CrossRef] [PubMed]
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. [CrossRef]
ATI, 2016, “ ATI Industrial Automation,” ATI Industrial Automation, Apex, NC, accessed Apr. 1, 2016, https://www.ati-ia.com/Products/ft/sensors.aspx
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. [CrossRef]
Thaweewat, N. , Phoemsapthawee, S. , and Juntasaro, V. , 2018, “ Semi-Active Flapping Foil for Marine Propulsion,” Ocean Eng., 147, pp. 556–564. [CrossRef]
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. [CrossRef]
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. [CrossRef] [PubMed]
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. [CrossRef] [PubMed]
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. [CrossRef]


Grahic Jump Location
Fig. 1

(a) sweep angle of flapping pectoral fins and (b) demonstration of significant impact of sweep angle (varied from 0 deg to 40 deg, in increment of 10 deg) on the fin geometry

Grahic Jump Location
Fig. 2

MantaDroid is propeled by the pectoral fins used for the study in this paper

Grahic Jump Location
Fig. 3

(a) a base fin design (fabricated one in black) with its dimensions and (b) fins of the five sweep angle variations

Grahic Jump Location
Fig. 4

The leading edge design

Grahic Jump Location
Fig. 5

Fin designs sorted according to their bending stiffness

Grahic Jump Location
Fig. 6

The experiment setup

Grahic Jump Location
Fig. 7

The normalized T represented by box charts for the base fin designs

Grahic Jump Location
Fig. 8

The average of the normalized T generated by the fins of the same thickness in freestream and still water, ignoring the effects of leading edge designs related to the spanwise flexibility

Grahic Jump Location
Fig. 9

The average of the normalized T generated by the fins of the same leading edge design in freestream (the top chart) and still water (the bottom chart), ignoring the effects of fin thickness related to the chordwise flexibility

Grahic Jump Location
Fig. 10

T∧ of the base fin designs. In each graph, a total of 80 data points, corresponding to the five sweep angles and 16 kinematic parameters, can be observed.

Grahic Jump Location
Fig. 11

An example of the measured angle of attack for two sweep angle variations 30 (left) deg and 40 (right) deg. The fins were of the same base fin design with thick fin and leading edge design 4. The fins are flapping with the same f and A.

Grahic Jump Location
Fig. 12

The concavity of the thrust generation patterns demonstrated by the coefficient of x2 from the polynomial representation of the patterns in Table 4

Grahic Jump Location
Fig. 13

The aligned3 thrust generation patterns of the thin and thick fins of the same leading edge design

Grahic Jump Location
Fig. 14

The average of the lateral force against the sweep angle

Grahic Jump Location
Fig. 15

Exemplification of the steps of process to obtain thrust generation pattern for the fin with sweep angle 0, leading edge Design 1, and thin PVC sheet; top left: categorization of T into four groups of ascending A, top right: T∧, bottom left: T∧ rearranged according to chord Reynolds number, and bottom right: thrust generation pattern

Grahic Jump Location
Fig. 16

Each graph shows five thrust profiles associated with the five sweep angles, generated under a certain f and A



Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In