The ancient art of laying rope

  title={The ancient art of laying rope},
  author={John C. Bohr and Kasper W. Olsen},
  journal={EPL (Europhysics Letters)},
  • J. BohrK. Olsen
  • Published 6 April 2010
  • Materials Science
  • EPL (Europhysics Letters)
We describe a geometrical property of helical structures and show how it accounts for the early art of rope-making. Helices have a maximum number of rotations that can be added to them — and it is shown that this is a geometrical feature, not a material property. This geometrical insight explains why nearly identically appearing ropes can be made from very different materials and it is also the reason behind the unyielding nature of ropes. Maximally rotated strands behave as zero-twist… 

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