By Meghan Bialt-DeCelie ’19

One of the most notable features of cephalopods like octopus and cuttlefish is their ability to quickly camouflage with the environment by changing the color and texture of their skin. They are able to dynamically adapt the textures of their skin by contracting muscular hydrostat structures referred to as papillae.

Researchers, led by James Pikul PhD, from Cornell University took inspiration from this biological feature to develop a synthetic tissue that could be controlled to rapidly change from a 2-dimensional structure to a range of textured 3-dimensional structures as cephalopods can. They constructed their synthetic skin with a fiber mesh arranged in a concentric circular pattern and silicone polymer with elastic properties. The elastomer is critical for temporary bending, stretching, and shaping to the mesh. The fiber provides the forces to shape the 3-dimensional structures while the silicone elastomer acts to reversibly stretch to the desired shapes.

The forces applied by the fiber mesh were controlled by a binary mechanism called Circumferentially Constrained and Radially Stretched Elastomer (CCOARSE) to design the range of 3D structures that their synthetic skin could form. By changing the patterns of the mesh they were able to accurately form various symmetric and nonsymmetrical patterns and textures that imitate natural structures like rocks and plants.

The researchers plan to investigate ways to improve resolution and accuracy of the patterns as well as the use of materials that could provide a different range of rigidity of the structure.

References:

1. J. Pikul, et al., Stretchable surfaces with programmable 3D texture morphing for synthetic camouflaging skins. Science 358, 210-214 (2017). doi: 10.1126/science.aan5627.
2. Image retrieved from: https://en.wikipedia.org/wiki/Common_octopus