Abstract
The mechanical properties and microstructural characteristics of elephant skin have been investigated in this study to gain insights into its exceptional robustness, deformability, and touch sensitivity. Specifically, skin samples from the elephant trunk were thoroughly analyzed to understand their morphology and inner structure. The mechanical behavior of different skin layers was assessed through uniaxial tensile and indentation tests, enabling the retrieval of their mechanical parameters. To better comprehend the microstructure of the skin, two simplified numerical models were developed. The first model elucidated the role of the discrete island-shaped structure of the epidermis, which allows the skin to elongate while maintaining its robustness. The second model focused on the epidermal ridges, demonstrating their influence in increasing local strain under indentation stimuli. These investigations into the natural properties of elephant skin have significant implications for the design of a new generation of artificial skins that exhibit remarkable sensitivity, toughness, and deformability. The findings presented in this study contribute to the advancement of biomimetic materials and inspire innovative approaches in various fields, ranging from robotics to prosthetics and beyond.
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Acknowledgments
The authors would like to thank the following people from the Istituto Italiano di Tecnologia: Seonggun Joe for the support in developing the experimental set up; Simone Lantean, Rosalia Bertorelli, and Maria Summa, for their support in samples’ preparation. The authors also would like to thank the Zoo Zurich (Switzerland) for providing the trunk of an Asian elephant and Henning Richter, Maya Kummrow and Jean-Michel Hatt at the Tierspital (Zurich, Switzerland) for CT scans of the Asian elephant trunk. This work received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 863212 (PROBOSCIS project).
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Kamare, B. et al. (2023). Study and Preliminary Modeling of Microstructure and Morphology of the Elephant Trunk Skin. In: Meder, F., Hunt, A., Margheri, L., Mura, A., Mazzolai, B. (eds) Biomimetic and Biohybrid Systems. Living Machines 2023. Lecture Notes in Computer Science(), vol 14158. Springer, Cham. https://doi.org/10.1007/978-3-031-39504-8_7
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