Morphogenesis
Growing structures can form complicated morphologies due to self- or external constrains. This is observed up from tiny structures like DNA up to the geological length scales. The morphological characteristics of these complex systems result from many interacting instabilities. These can be observed in quite different systems, like growing strings in two- and three dimensional rigid or elastic confinements, of shells with self constraint or confined growth, in pressurized systems like pollen tubes, or spherical capsids, where shell orthotropy determines morphologies. As standard methods do not work for such systems with massive self-contact, buckling, wrinkling, folding and growth, we developed own implementations for 3D beam and subdivision surface shell Finite Element representations.
Outreach:
- G. Munglani, F.K. Wittel, R. Vetter, F. Bianchi, H.J. Herrmann: Collapse of orthotropic spherical shells, Physical Review Letters 123 (2019) 058002.
- C. Hu, G. Munglani, H. Vogler, F.K. Wittel, C. Eichenberger, U. Grossniklaus, B.K. Nelson, H.J. Herrmann: Characterization of size-dependent mechanical properties of tip-growing cells using a lab-on-chip device, Lab on a Chip 17 (2017), 82-90.
- Vetter, F.K. Wittel, H.J. Herrmann: Packing of elastic wire in flexible shells, European Physics Letters 112 (2015), 44003.
- G. Munglani, R. Vetter, F.K. Wittel, H.J. Herrmann: Orthotropic Rotation-free Thin Shell Elements , Computational Mechanics 56 (2015), 785-793.
- R. Vetter, F.K. Wittel, H.J. Herrmann: Morphogenesis of filaments growing in flexible confinements. Nature Communications 5 (2014), 4437.
- R. Vetter, N. Stoop, F.K. Wittel, H.J. Herrmann: Simulating Thin Sheets: Buckling, Wrinkling, Folding and Growth, Journal of Physics: Conference Series (JPCS) 487 (2014), 012012.
- R. Vetter, F.K. Wittel, N. Stoop, H.J. Herrmann: Finite element simulation of dense wire packings, European Journal of Mechanics - A/Solids 37 (2013), 160-171.
- R. Vetter, N. Stoop, T. Jenni, F.K. Wittel, H.J. Herrmann: Subdivision Shell Elements with Anisotropic Growth, International Journal for Numerical Methods in Engineering 95 (2013), 791-810.
- J. Najafi, N. Stoop, F. Wittel, M. Habibi: Ordered packing of elastic wires in a sphere, Physical Review E 85 (2012), 061108.
- N. Stoop, J. Najafi, F. K. Wittel, M. Habibi, and H. J. Herrmann: Packing of Elastic Wires in Spherical Cavities, Physical Review Letters 106 (2011), 214102.
- N. Stoop, F.K. Wittel, and H.J. Herrmann: Self-contact and instabilities in anisotropic growth of soft tissue, Physical Review Letters 105 (2010), 068101.
- N. Stoop, F.K. Wittel, H.J. Herrmann: Morphological Phases of Crumpled Wire, Physical Review Letters 101 (2008), 094101.
- Faltungslehre: Kalligraphie mit Metallschlaufen. FAZ 19.9.2008
Funding by ETH research grants and SNF SystemsX grant.