A new octopus-inspired adhesive that can precisely grip and release objects underwater has been developed by a team of researchers from Virginia Tech.

In addition to having potential applications in underwater salvage and rescue operations, the new adhesive promises to help divers hold slippery objects without squeezing them too hard, according to its developers.

Source: Alex Parrish/Virginia Tech Source: Alex Parrish/Virginia Tech

To develop the adhesive, the Virginia Tech team first examined the outermost region of the octopus’s sucker, which is called the infundibulum. Because this part is composed of living tissue, the infundibulum can adjust its shape and strength to suit the object in its grasp, regardless of the object’s texture and shape. Based on this finding, the team developed a multi-surface adhesive using an elastic, curved stalk along with a deformable membrane.

The researchers determined that the adhesive is capable of attaching to rough, curved, irregular surfaces and different fluids with exceptional strength.

“This resulted in octopus-inspired adhesives that are 1,000 times stronger when activated compared to the easy release state. Importantly, this switch occurs within a fraction of a second, about 30 milliseconds,” the researchers explained.

The team demonstrated the effectiveness of the adhesive by using it in the construction of an “underwater cairn” using a pile of rocks of various sizes, shapes and textures.

During trials, the adhesive demonstrated “reliable attachment” over many uses and prolonged periods. During one such trial, the adhesive maintained its strength through 100 cycles and even held a rough rock underwater for more than one week and subsequently released it on command.

The material is detailed in the article, “Octopus-Inspired Adhesives with Switchable Attachment to Challenging Underwater Surfaces,” which appears in the journal Advanced Science.

To contact the author of this article, email mdonlon@globalspec.com