278
fi ns: median, which are along the body center line, and those that are paired (Lauder
and Madden 2006 ). Their fl exibility is important for thrust production and vectoring
forces. Thus, fi shes mostly possess two sets of paired fi ns, the pelvics and pectorals ,
and three median fi ns, the dorsal , anal and caudal fi n . Recent work showed that the
fi sh’s locomotion mechanism is mainly controlled by its paired pectoral fi ns and
caudal fi n (Lauder and Drucker 2004 ; Westneat et al. 2004 ). Due to the special
structure and unique material properties of their fi ns, fi shes are effi cient swimmers,
and possess high manoeuvrability. Fish are “able to follow trajectories, can effi ciently
stabilize themselves in currents and surges, create fewer wakes, and have noiseless
propulsion,” (Sitorus et al. 2009 ).
I would like to direct your attention to the fact that fi sh can also fl y! A few marine
fi sh are not only swimmers, but possess the ability to fl y and glade over the sea
surface. So, fl ying-fi sh aerodynamics (Latimer-Needham 1951 ; Fish 1999 ) is of the
same scientifi c importance as swimming fi sh hydrodynamics. Therefore, it’s not
surprising that there is growing interest in researching mechanical and control
system for fl ying robotics, as well as for underwater vehicles using fi sh fi ns as
sources for bioinspiration. “These ongoing research efforts are motivated by more
pervasive applications of such vehicles, including: seabed oil and gas explorations,
scientifi c deep ocean surveys, military purposes, ecological and water environmental
studies,” ( Sitorus et al. 2009 ), and also for entertainment (see for review Sfakiotakis
et al. 1999 ; Mittal 2004 ; Kato et al. 2005 ; Kodati 2006 ; Lauder et al. 2011 ).
7.1 Fish Fins and Rays: Diversity, Structure and Function
Over than 28,000 of fi sh species are related to ray-fi nned fi shes, which are known
for their diversity in locomotory styles (Lauder and Drucker 2004 ; Lauder 2006 ;
Alben et al. 2007 ). Ray-fi nned fi sh due to both median (midline) and paired fi ns
( Fig. 7.1 ) can control their body position and generate force during locomotion.
The main types of fi ns are as follows: dorsal fi ns, caudal fi n, pectoral fi ns, pelvic
fi ns, anal fi n, adipose fi n and fi nlets. Finlets in birchis, for example, are represented
in the form of small fi ns located only on the dorsal surface.
According Lauder et al. ( 2012 ), “fi sh species vary in body stiffness, and in how the
body is moved during swimming,” (Lauder et al. 2012 ), by the manner in which these
types of fi ns are used. Webb ( 1988 ) classifi es all swimming vertebrae in four classes:
– Class A uses body and/or caudal fi ns (BCF) for periodic propulsion and is best
suited for long-term swimming at relatively high speeds.
– Class B uses body and/or caudal fi ns for transient propulsion, well suited for
quick starts and turns. The bodies of members of this class are fl exible and have
a large tail area.
– Class C uses median and/or paired fi ns (MPF) for slow swimming and precise
manoeuvring, and has better effi ciency at low speeds.
– Class D include those fi sh that swim only rarely (see also for review Sitorus
et al. 2009 ).
7 Fish Fins and Rays as Inspiration for Materials Engineering and Robotics
fi ns: median, which are along the body center line, and those that are paired (Lauder
and Madden 2006 ). Their fl exibility is important for thrust production and vectoring
forces. Thus, fi shes mostly possess two sets of paired fi ns, the pelvics and pectorals ,
and three median fi ns, the dorsal , anal and caudal fi n . Recent work showed that the
fi sh’s locomotion mechanism is mainly controlled by its paired pectoral fi ns and
caudal fi n (Lauder and Drucker 2004 ; Westneat et al. 2004 ). Due to the special
structure and unique material properties of their fi ns, fi shes are effi cient swimmers,
and possess high manoeuvrability. Fish are “able to follow trajectories, can effi ciently
stabilize themselves in currents and surges, create fewer wakes, and have noiseless
propulsion,” (Sitorus et al. 2009 ).
I would like to direct your attention to the fact that fi sh can also fl y! A few marine
fi sh are not only swimmers, but possess the ability to fl y and glade over the sea
surface. So, fl ying-fi sh aerodynamics (Latimer-Needham 1951 ; Fish 1999 ) is of the
same scientifi c importance as swimming fi sh hydrodynamics. Therefore, it’s not
surprising that there is growing interest in researching mechanical and control
system for fl ying robotics, as well as for underwater vehicles using fi sh fi ns as
sources for bioinspiration. “These ongoing research efforts are motivated by more
pervasive applications of such vehicles, including: seabed oil and gas explorations,
scientifi c deep ocean surveys, military purposes, ecological and water environmental
studies,” ( Sitorus et al. 2009 ), and also for entertainment (see for review Sfakiotakis
et al. 1999 ; Mittal 2004 ; Kato et al. 2005 ; Kodati 2006 ; Lauder et al. 2011 ).
7.1 Fish Fins and Rays: Diversity, Structure and Function
Over than 28,000 of fi sh species are related to ray-fi nned fi shes, which are known
for their diversity in locomotory styles (Lauder and Drucker 2004 ; Lauder 2006 ;
Alben et al. 2007 ). Ray-fi nned fi sh due to both median (midline) and paired fi ns
( Fig. 7.1 ) can control their body position and generate force during locomotion.
The main types of fi ns are as follows: dorsal fi ns, caudal fi n, pectoral fi ns, pelvic
fi ns, anal fi n, adipose fi n and fi nlets. Finlets in birchis, for example, are represented
in the form of small fi ns located only on the dorsal surface.
According Lauder et al. ( 2012 ), “fi sh species vary in body stiffness, and in how the
body is moved during swimming,” (Lauder et al. 2012 ), by the manner in which these
types of fi ns are used. Webb ( 1988 ) classifi es all swimming vertebrae in four classes:
– Class A uses body and/or caudal fi ns (BCF) for periodic propulsion and is best
suited for long-term swimming at relatively high speeds.
– Class B uses body and/or caudal fi ns for transient propulsion, well suited for
quick starts and turns. The bodies of members of this class are fl exible and have
a large tail area.
– Class C uses median and/or paired fi ns (MPF) for slow swimming and precise
manoeuvring, and has better effi ciency at low speeds.
– Class D include those fi sh that swim only rarely (see also for review Sitorus
et al. 2009 ).
7 Fish Fins and Rays as Inspiration for Materials Engineering and Robotics