By Sandra Cabangon

A glove inspired the cover of Science Advances journal’s July 13 edition for no simple feat — this glove allows users to pick up things underwater with the use of sensors and suckers, mimicking an octopus’ tentacles. Named after the underwater creature that inspired its creation, the innovation is named Octa-Glove.

Photo Courtesy of Alex Parrish for Virginia Tech

Octa-Glove was created by a research team led by Michael Bartlett, a mechanical engineer from Virginia Tech. According to Bartlett, the unique properties of the octopus would be very useful for many fields in science. “Being able to grasp things underwater could be good for search and rescue, it could be good for archaeology, [and] could be good for marine biology.”

While focus on other underwater equipment such as tanks and goggles is evident, the issue of picking up objects underwater remains. Those who use their hands to retrieve objects, such as rescue divers and underwater archaeologists, encounter difficulties when doing their tasks. Greater force can be exerted, but it becomes a problem when handling fragile objects.

“Nature already has some great solutions, so our team looked to the natural world for ideas. The octopus became an obvious choice for inspiration,” Bartlett said.

Each finger is equipped with raspberry-sized cones that can be likened to that of the approximately 2000 suckers on octopuses' limbs. These cones are made of rubber and contain flexible membranes that allow the cones to stick to objects. Meanwhile, a micro-LIDAR sensor — a type of sensor that is capable of measuring the distance of an object from as close as to 10 centimeters and as far as 12 meters — detects how close the objects are. 

Then, a microcontroller triggers the sucker to stick to the object when it is detected at a programmed distance. These suckers and sensors are synthetically programmed to give users a natural feel when holding the objects. It also makes the gloves adaptable to the environment.

“It makes handling wet or underwater objects much easier and more natural. The electronics can activate and release adhesion quickly. Just move your hand toward an object, and the glove does the work to grasp. It can all be done without the user pressing a single button,” Bartlett said.

The glove has been tested using several objects, such as a toy car, plastic spoon, an ultrasoft hydrogel ball, a box, and a metal bowl. At first, it could easily pick up and release flat objects, cylinders, metal toys, and a hydrogel ball. After improvement and recalibration, it could grip larger objects like a plate, a box, and a bowl. It can even pick up objects weighing one kilogram in open air and even more underwater because of buoyancy. Flat and curved surfaces present no problem be it underwater or in air, but it encounters difficulty picking up rough objects when a proper seal can’t be formed by the sucker and it cannot attach to the object properly.

The conception of Octa-Glove presents many possibilities for future scientific endeavors. At present, Octa-Glove picks up anything that comes within a certain distance. However, the creators consider adding chemical sensors so that the suckers only stick to certain materials, like the chemical-detecting cells that allow an octopus to “taste” or collect more information about their environment. In addition, Bartlett eyes the possible future uses of their creation, such as in manufacturing and healthcare.

“The glove was a natural starting point for us. I thought it would be neat to have octopus-like abilities on your hand,” Bartlett said. “But we could also make an arm which is more like a tentacle — we could actually make it very biometric.”

Postdoctoral researcher Ravi Tutika acknowledged the innovation’s contribution to science. “These capabilities mimic the advanced manipulation, sensing, and control of cephalopods and provide a platform for synthetic underwater adhesive skins that can reliably manipulate diverse underwater objects,” Tutika said. “This is certainly a step in the right direction, but there is much for us to learn both about the octopus and how to make integrated adhesives before we reach nature’s full gripping capabilities.”