title: Spatial model of the gecko foot hair: functional significance of highly specialized non-uniform geometry.
abstract: One of the important problems appearing in experimental realizations of artificial adhesives inspired by gecko foot hair is so-called clusterization. If an artificially produced structure is flexible enough to allow efficient contact with natural rough surfaces, after a few attachment-detachment cycles, the fibres of the structure tend to adhere one to another and form clusters. Normally, such clusters are much larger than original fibres and, because they are less flexible, form much worse adhesive contacts especially with the rough surfaces. Main problem here is that the forces responsible for the clusterization are the same intermolecular forces which attract fibres to fractal surface of the substrate. However, arrays of real gecko setae are much less susceptible to this problem. One of the possible reasons for this is that ends of the seta have more sophisticated non-uniformly distributed three-dimensional structure than that of existing artificial systems. In this paper, we simulated three-dimensional spatial geometry of non-uniformly distributed branches of nanofibres of the setal tip numerically, studied its attachment-detachment dynamics and discussed its advantages versus uniformly distributed geometry.
authors: Functional Morphology and Biomechanics, Zoological Institute , Kiel University , 24118 Kiel , Germany ; Department of Electronic and Kinetic Properties of Non-linear Systems , Donetsk Institute for Physics and Engineering, National Academy of Sciences , 83114 Donetsk , Ukraine.
authors: Alexander E
authors: AE
authors: Filippov
authors: Functional Morphology and Biomechanics, Zoological Institute , Kiel University , 24118 Kiel , Germany.
authors: Stanislav N
authors: SN
authors: Gorb
keywords: bioadhesion; biological adhesives; clusterization; fibrillar adhesives; gecko seta
references: Acta Biomater. 2005 Jan;1(1):5-13
references: 16701776
references: J Theor Biol. 2011 May 7;276(1):126-31
references: 21295591
references: Ultramicroscopy. 2007 Oct;107(10-11):902-12
references: 17555877
references: Integr Comp Biol. 2002 Dec;42(6):1140-5
references: 21680398
references: Chem Commun (Camb). 2005 Aug 14;(30):3799-801
references: 16041421
references: Proc Natl Acad Sci U S A. 2002 Sep 17;99(19):12252-6
references: 12198184
references: Phys Rev E Stat Nonlin Soft Matter Phys. 2007 Feb;75(2 Pt 2):027103
references: 17358452
references: Proc Natl Acad Sci U S A. 2003 Sep 16;100(19):10603-6
references: 12960386
references: Biol Lett. 2005 Mar 22;1(1):2-4
references: 17148113
references: Proc Natl Acad Sci U S A. 2004 May 25;101(21):7851-6
references: 15148400
references: Phys Rev E Stat Nonlin Soft Matter Phys. 2007 Jun;75(6 Pt 2):066104
references: 17677322
references: J R Soc Interface. 2006 Jun 22;3(8):441-51
references: 16849272
references: Nature. 2000 Jun 8;405(6787):681-5
references: 10864324