Scientific Programme

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Mechanical behavior of plant wings

Monday (16.03.2020)
17:37 - 17:38
Part of:

Session P.2: Poster Session
Belongs to:
General Topic Poster

Auto-rotating winged seeds, such as tree samara, incorporate self-generating aerodynamic lift forces that reduce their falling velocities upon detachment from the tress, and enable their passive dispersal into distance places by occasional winds. The small-scale wing element of these samaras are supposed to elastically resist both the autorotation-induced and the wind-induced aerodynamic forces to prevent undesired structural deformations that will deter their flying capabilities. We analyzed experimentally the mechanical behavior of the wing of the Tipuana Tipu samara, both in terms of their macroscopic properties (structural compliance) and material-level properties (nanoscale modulus). We quantified experimentally the local structural compliance of the wing element by point-force bending experiments, and derived closed-form analytical formula that expresses the overall compliance behavior of the wing element. Additionally, we used nanoindentation to measure the elastic modulus of the underlying wing material and found that the anisotropic material properties are preserved in different locations within the wing, but the local orientation of the material substantially varies across the wing, and are thus a major parameter that dominate the wing structural compliance. Understanding the structural–mechanical principles of the samara wings may pave the way to the design of high-performance, small-scale wing elements for advanced unmanned aerial vehicles.

Liat Levavi
Ben-Gurion University of the Negev
Additional Authors:
  • Dr. Benny Bar-On
    Ben-Gurion University of the Negev
  • Zeneve Ezra
    Ben-Gurion University of the Negev