Bio-inspired active patterned surfaces

Attachment and detachment is a common phenomenon that lie in the vicinity of the contact interfaces and advantages several natural species for their survival, for instance, Geckos, tree frog or octopuses. The fundamentals of attachment might differ from one species toother; for instance the attachment is possible due to van der Waals interactions between themicro-nanometric pattern on the toe of a Gecko and the wall, see Figure 1(a) [1]. In case of tree frog the attachment is mainly due to the capillary forces [2] and for octopus it is viasuction pressure generated by the muscles of the octopus [3]. But, have you ever thought despite reliable attachment of these animals onto the surfaces, how they are able to control the attachment and detachment?

The attaching features in the animals are in general soft and patterned onto a soft tissues. The process of detachment is mainly controlled via controlling the communication between the patterned features which is responsible for local or global distribution of the load released during detachment. In this project you will explore the active mechanisms to control the attachment and detachment process of soft interfaces for the soft robotic applications.

Figure 1: (a) A picture of a Gecko along with SEM pictures of its toe showing micro and-nanometric pattern, and (b) attachment of a patterned surface on a textile fabric.
Figure 1: (a) A picture of a Gecko along with SEM pictures of its toe showing micro and-nanometric pattern, and (b) attachment of a patterned surface on a textile fabric.

Aim

The goals of this project is to develop active functional soft surfaces with the ability to control adhesion. You will explore the active mechanism for instance granular jamming mechanism [4], to play with the interfacial adhesion of patterned surfaces as shown in Figure 1(b). Depending on the interest of the student there is a possibility to work on the computer simulation as well for exploring the interfacial dynamics of the detachment features.

Methods/Techniques to be used

  • 3D printers, soft-lithography
  • SolidWorks, CAD 3D software
  • Adhesion meter, rheometer, tribometer
  • Camera/Microscope

This proposal is an opportunity for a student to work on an existing research project going on in our lab. You can read the ref. [5] for an overview of the research you will be involved with. Basic knowledge of Python/Matlab, imageJ, CAD software will be highly appreciated. Your hard work and enthusiasm during the project might end-up with a publication.

Contact person

Please write to Preeti Sharma for further questions.

References:

[1] S. N. Gorb, “Biological attachment devices: exploring nature’s diversity for biomimetics”, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 366, 1557 (2008).

[2] J. K. Langowski, D. Dodou, M. Kamperman, and J. L. van Leeuwen, “Tree frog attach-ment: mechanisms, challenges, and perspectives”, Frontiers in zoology 15, 1 (2018).

[3] F. Tramacere, A. Kovalev, T. Kleinteich, S. N. Gorb, and B. Mazzolai, “Structure and mechanical properties of ¡i¿octopus vulgaris¡/i¿ suckers”, Journal of The Royal Society Interface 11, 20130816 (2014).

[4] E. Brown, N. Rodenberg, J. Amend, A. Mozeika, E. Steltz, M. R. Zakin, H. Lipson, andH. M. Jaeger, “Universal robotic gripper based on the jamming of granular material”, Proceedings of the National Academy of Sciences 107, 18809 (2010).

[5] P. Sharma, V. Saggiomo, V. van der Doef, M. Kampermaan, and J. A. Dijksman, “Hooked on mushrooms: preparation and mechanics of a bioinspired soft probabilisticfastener”, Biointerphases 16, 10.1116/6.0000634 (2020).