Abstract
The objectives of this study were the development of a new device for maneuvering an underwater vehicle using the mechanism of a fish swimming, an experimental and theoretical analysis of the hydrodynamic characteristics of the device, and its application to maneuvering a fish robot. Observations and experimental analysis of the pectoral fins of a black bass (Micropterus salmoides) revealed that the locomotion of the fish, such as swimming forward at low speed, swimming backward, and turning in a horizontal plane is generated by using a combination of a feathering motion and a lead-lag motion of the pectoral fins. A mechanical pectoral fin making a feathering motion and a lead-lag motion generates a thrust force in a range of phase differences between both motions. The unsteady vortex lattice method, including the effect of viscosity, can express fairly well the unsteady forces acting on the mechanical pectoral fin in the range of phase differences where it exerts the thrust force. The fish robot, consisting of a model fish body and a pair of mechanical pectoral fins, can not only swim forward and turn in almost the same position, but can also swim in a lateral direction without changing the yaw angle.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Abbreviations
- c :
-
chord length of pectoral fin
- C x ,C y ,C z ,C my ,C mz :
-
hydrodynamic force coefficients
- F x ,F y ,F z ,M y ,M z :
-
hydrodynamic forces
- F x0 ,M y0 ,M z0 :
-
hydrodynamic forces acting on support setups alone without fin
- K :
-
nondimensional frequency
- L :
-
length of fish
- n P :
-
normal unit vector to surface of pectoral fin
- Oe :
-
field out of pectoral fin
- p :
-
pressure on pectoral fin
- r QP :
-
position vector of pointP where the velocity field is calculated from pointQ on the singularity
- r p :
-
position vector of pointP from pointO
- Re :
-
Reynolds number
- S :
-
surface area of pectoral fin
- S fin :
-
surface of pectoral fin
- T :
-
period of motion
- t :
-
time
- t 0 :
-
time when a free vortex filament is shed
- T s :
-
strength of the bound vortex sheet on the pectoral fin
- U :
-
advancing velocity
- U :
-
inflow velocity vector
- V ω :
-
vortical field
- V e :
-
external velocity field outside pectoral fin
- V p :
-
velocity vector
- w :
-
induced velocity vector from a vortex filament
- W 0Y W 0Z :
-
mean value of tangential velocity in theY″ direction and in theZ″ direction, respectively, on a pectoral fin normal to theX″, axis
- (X, Y, Z), (X′, Y′, Z′), (X″, Y″, Z″) :
-
coordinate systems of the mechanical pectoral fin
- x′:
-
measured span on the monitor
- y′:
-
cord length on the monitor
- z′:
-
projected chord length on the monitor, dorsal view
- α:
-
feathering angle
- α1, α2:
-
angles defined in Fig. 10
- \(\dot \alpha\) :
-
angular velocity of feathering angle
- β:
-
lead-lag angle
- \(\dot \beta\) :
-
angular velocity of lead-lag angle
- ΔCp :
-
pressure difference coefficient
- Y y ,Y z :
-
line density of bound vortex sheet in theY″ direction and in theZ″ direction, respectively
- Γ:
-
circulation around pectoral fin
- Γ f :
-
circulation of free vortex filament
- η:
-
thrust effeciency
- σ:
-
nondimensional frequency
- v :
-
kinematic viscosity
- V E :
-
effective kinematic viscosity
- ω fin :
-
angular velocity
- ω fin :
-
angular velocity vector of pectoral fin
- \(\bar \omega\) :
-
vorticity inV ω
- x:
-
vector product
- +:
-
face side of pectoral fin
- −:
-
back side of pectoral fin
References
Kato N, Lane DM (1995) Coordinated control of multiple manipulators in underwater robots. Proceedings of the 9th International Sympasium on Unmanned, Untethered Submersible Technology, pp. 34–50.
Hertel H (1996) Structure-form-movement. Reinhold, New York.
Isshiki N, Morikawa H (1982) Study on dolphin-style fin ship (in Japanese). Bull Soc Nav Archit Jpn 642:2–9
Barrett DS, Triantafyllou MS (1995) The design of flexible hull undersea vehicle properlled by an oscillating foil Proceedings of the 9th International Symposium on Unmanned, Untethered Submersible Technology, pp 111–123
Tanaka I, Nagai M (1996) Hydrodynamics of drag and propulsion—learning from high speed swimming performance of aquatic animals (in Japanese). Ship and Ocean Foundation.
Bandyopadhyay PB, Castano JM, Rice JQ et al. (1997) Low-speed maneuvering hydrodynamics of fish and small underwater vehicles. J Fluids Eng, Trans ASME 119:136–144
Lindsey CC (1978) Form, function and locomotion habits in fish. In: Hoar W, Randall DJ (eds) Fish physiology VII. Academic Press, New York, pp 239–313
Webb PW (1982) Locomotor patterns in the evolution of Actinopterygian fishes. Am Zool 22:329–342
Webb PW (1984) Body form, locomotion and foraging in aquatic vertebrates. Am Zool 24:107–120
Blake RW (1979) The mechanics of labriform locomotion. I. Labriform locomotion in the angelfish (Pterophyllum eimekei): an analysis of the power stroke. J Exp Biol 82:255–271
Webb PW (1973) Kinematics of pectoral fin propulsion inCymatogaster agregata. J Exp Biol 59:697–710
Yates GT (1983) Hydromechanics of body and candal fin propulsion. In: Webb PW, Weihs D (eds) Fish biomechanics, Pragaeyer, New York
Kato N, Yamaguchi M (1985) The vortex on a submerged solid of revolution. 2nd International Sympasium on Ship Viscous Resistance, pp 22:1–22:22
Author information
Authors and Affiliations
Additional information
Translation of an article that appeared in the Journal of The Society of Naval Architects of Japan, vol. 182 (1997): The original article won the SNAJ prize, which is awarded annually to the best papers selected from the SNAJ Journal, JMST, or other quality journals in the field of naval architecture and ocean engineering.
About this article
Cite this article
Kato, N. Locomotion by mechanical pectoral fins. J Mar Sci Technol 3, 113–121 (1998). https://doi.org/10.1007/BF02492918
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02492918