Hemihelix

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Animatic of a Rotating Hemihelix Animatic of a Rotating Hemihelix.gif
Animatic of a Rotating Hemihelix
Video recording for a hemihelix with one perversion under water. Both ends are free to rotate.

A hemihelix is a curved geometric shape consisting of a series of helices with alternating chirality, connected by a perversion at the reversals. [1] [2]

The formation of hemihelices with periodic distributions of perversions in slender structures is understood in terms of competing buckling instabilities generated by in-plane stresses. [3]

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References

  1. Amina Khan (April 24, 2014). "With a little rubber, scientists make weird, twisted hemihelix". Los Angeles Times.
  2. Lydia Smith (April 24, 2014). "Scientists Discover New Rare 'Hemihelix' Shape Using Rubber Bands". International Business Times.
  3. Liu, J.; Huang, J.; Su, T.; Bertoldi, K.; Clarke, D. R. (2014). "Structural Transition from Helices to Hemihelices". PLOS ONE. 9 (4): e93183. Bibcode:2014PLoSO...993183L. doi:10.1371/journal.pone.0093183. PMC   3997338 . PMID   24759785.