277
© Springer Science+Business Media Dordrecht 2015
H. Ehrlich, Biological Materials of Marine Origin, Biologically- Inspired Systems 4,
DOI 10.1007/978-94-007-5730-1_7
Chapter 7
Fish Fins and Rays as Inspiration
for Materials Engineering and Robotics
Abstract Marine fi sh show unique properties: they can move in both water and air.
These properties are determined by numerous factors like body and skin shape, fi ns
and tails, rays and ray-like structures, and muscles. The diversity, structure and function of fi sh fi ns and rays, including an analysis of the specifi c biological materials they
are made of, are discussed in this chapter. Special attention is payed to biomimetics
and bioinspiration for fi sh robotics and devices. This chapter also aims to explore the
possibilities for fi elds such as fi sh fi n regeneration and tissue engineering.
According modern point of view, “the gradual mineralization of the vertebral
elements, appearance of fi n rays and new median fi ns, and transverse and then
horizontal segmentation of the axial musculature are all features correlated with
increases in swimming speed, manoeuvrability, and body size of early chordates
and vertebrates,” (Koob and Long 2000 ). Thus, most teleost fi sh are obligate axial
swimmers (Nelson 1994 ) and swim by oscillating or laterally undulating their
body and propulsive caudal fi n. The role of muscles during swimming is briefl y
described by Ann Pabst as follow:
“Axial muscles, arranged in complexly folded myomeres, transmit contractile
forces via the connective tissue ‘fabrics’ of myosepta, horizontal and vertical septa,
and skin. These forces do work against a variably fl exible beam, the vertebral
column, to affect swimming movements. Myomeres and myosepta are connected
directly to the dermis of the skin, as well as to the vertebral column. The function of
the myomeres is to produce lateral bending in the axial skeleton. During steady
swimming, the pattern of muscle activity is both unilateral and uniphasic—at any
point along the body, muscles on only one side of the animal are active at a time, and
there is only one bout of muscle activity per side, per locomotor cycle,” (Ann Pabst
2000 ; see also Wainwright 1983 ; Westneat et al. 1993 ).
The structure and function of fi sh muscles, which are involved in swimming, is
not the subject of this book. However, fi sh fi ns are crucial biocomposite-containing
structures, which are the main players in swimming phenomena and therefore are
under discussion in this chapter. The dynamic interaction between the fi n and the
water is determined due to existence of the forces created especially by highly
deformable, ray-fi nned fi ns. Briefl y, “the fi n moves, pushes against the water, bends,
stores and releases energy, and creates vortices and jets that are shed into the fl ow,”
(Tangorra et al. 2011 ). Fish locomotion is based on activity of two major classes of
© Springer Science+Business Media Dordrecht 2015
H. Ehrlich, Biological Materials of Marine Origin, Biologically- Inspired Systems 4,
DOI 10.1007/978-94-007-5730-1_7
Chapter 7
Fish Fins and Rays as Inspiration
for Materials Engineering and Robotics
Abstract Marine fi sh show unique properties: they can move in both water and air.
These properties are determined by numerous factors like body and skin shape, fi ns
and tails, rays and ray-like structures, and muscles. The diversity, structure and function of fi sh fi ns and rays, including an analysis of the specifi c biological materials they
are made of, are discussed in this chapter. Special attention is payed to biomimetics
and bioinspiration for fi sh robotics and devices. This chapter also aims to explore the
possibilities for fi elds such as fi sh fi n regeneration and tissue engineering.
According modern point of view, “the gradual mineralization of the vertebral
elements, appearance of fi n rays and new median fi ns, and transverse and then
horizontal segmentation of the axial musculature are all features correlated with
increases in swimming speed, manoeuvrability, and body size of early chordates
and vertebrates,” (Koob and Long 2000 ). Thus, most teleost fi sh are obligate axial
swimmers (Nelson 1994 ) and swim by oscillating or laterally undulating their
body and propulsive caudal fi n. The role of muscles during swimming is briefl y
described by Ann Pabst as follow:
“Axial muscles, arranged in complexly folded myomeres, transmit contractile
forces via the connective tissue ‘fabrics’ of myosepta, horizontal and vertical septa,
and skin. These forces do work against a variably fl exible beam, the vertebral
column, to affect swimming movements. Myomeres and myosepta are connected
directly to the dermis of the skin, as well as to the vertebral column. The function of
the myomeres is to produce lateral bending in the axial skeleton. During steady
swimming, the pattern of muscle activity is both unilateral and uniphasic—at any
point along the body, muscles on only one side of the animal are active at a time, and
there is only one bout of muscle activity per side, per locomotor cycle,” (Ann Pabst
2000 ; see also Wainwright 1983 ; Westneat et al. 1993 ).
The structure and function of fi sh muscles, which are involved in swimming, is
not the subject of this book. However, fi sh fi ns are crucial biocomposite-containing
structures, which are the main players in swimming phenomena and therefore are
under discussion in this chapter. The dynamic interaction between the fi n and the
water is determined due to existence of the forces created especially by highly
deformable, ray-fi nned fi ns. Briefl y, “the fi n moves, pushes against the water, bends,
stores and releases energy, and creates vortices and jets that are shed into the fl ow,”
(Tangorra et al. 2011 ). Fish locomotion is based on activity of two major classes of