Have you ever lost your grip on something you dropped in the pool, or worse, toilet?
Scientists may have developed a solution for holding underwater objects, but it is not primarily intended to help you iPhone of a watery fate.
Researchers at Virginia Tech has developed a glove that allows divers to get a firm grip, for example when rescuing someone or salvaging a shipwreck.
The ‘octa glove’ is inspired by the tentacles of an octopus and is covered with robotic pistons equipped with sensors that can see how far away an object is.
When the sensors detect a nearby surface, it sends a signal to the controller that activates the suction cup adhesion.
The researchers hope the glove can be used for underwater operations that require a delicate touch.
Virginia Tech researchers have developed a glove that allows divers to get a firm grip when rescuing someone or salvaging a shipwreck, for example. Pictured is the octa-glove picking up a Virginia Tech playing card underwater
The glove’s suction cups are designed to adhere with just light pressure to flat, curved, smooth and rough surfaces on objects of various shapes and sizes – just like an octopus would
An octopus has eight long arms capable of gripping objects of any type of surface in a water environment, which proved to be the inspiration for the octa glove
Humans are not naturally equipped to work underwater, which is why goggles and wetsuits were invented, and our smooth skin is no exception.
Rescue divers, underwater archaeologists, bridge engineers and salvage crews all rely on a good grip to do their jobs.
However, sometimes it is necessary to tighten the grip to compensate for slipperiness, which can compensate for the surgery.
Michael Bartlett, an assistant professor of mechanical engineering, said, “There are critical times when this becomes a liability.
“Nature already has some great solutions, so our team looked to the natural world for ideas.
“The octopus became an obvious choice for inspiration.”
An octopus has eight long arms that can hold objects of any type of surface in an aquatic environment.
The arms are covered with suction cups shaped like the tip of a plunger, which are controlled by the marine animal’s muscular and nervous system.
After the wide outer rim of the suction cup makes a seal with an object, the octopus can use its muscles to contract or relax the cup-shaped area behind the rim to add or reduce pressure.
When many of the suction cups are engaged, a strong adhesive bond is created that is difficult to escape.
“When we look at the octopus, the glue definitely stands out, it activates quickly and releases the suture on demand,” Bartlett said.
“What’s just as interesting, however, is that the octopus controls more than 2,000 suction cups across eight arms by processing information from various chemical and mechanical sensors.
“The octopus brings together the tunability, detection and control of adhesion to manipulate underwater objects.”
After the wide outer rim of the suction cup makes a seal with an object, the octopus can use its muscles to contract or relax the cup-shaped area behind the rim to add or reduce pressure
Illustration of an octopus glue system and the sensorized, octopus-inspired glue system. The latter is integrated with processing and control to sense objects
Suction cups and sensors were added to the glove and connected via a microcontroller, mimicking the nervous system and muscles of an octopus. The suction cups stick when they sense an object is close, so no effort is required from the glove user
The team in the Soft Materials and Structures Lab developed their own suction cups with flexible, rubber stems covered with soft membranes.
Their method was published today in the journal scientific progress†
The suction cups are designed to adhere with just light pressure to flat, curved, smooth and rough surfaces on objects of various shapes and sizes – just like an octopus would in the wild.
Eric Markvicka of the University of Nebraska-Lincoln then added an array of micro-LIDAR optical proximity sensors that detect how close an object is.
The suction cups and LIDAR sensors were then connected via a microcontroller, mimicking the nervous system and muscles of an octopus.
“By joining soft, responsive adhesive materials with embedded electronics, we can grip objects without having to squeeze,” Bartlett says.
“It makes handling wet or underwater objects much easier and more natural. The electronics can quickly activate and release adhesion.
‘Just move your hand towards an object and the glove does the work for gripping.
‘It can all be done without the user pressing a single button.’
After attaching the suction cups to a glove, the engineers tested them on delicate and lightweight objects using only one sensor
The engineers found that the glove could quickly pick up and release flat objects, metal toys, cylinders, the double-curved part of a spoon, and an ultra-soft hydrogel ball.
Schematics showing the different states of the adhesive membrane controlling adhesion from an ‘off’ to ‘on’ state
After attaching the suction cups to a glove, the engineers tested them on delicate and lightweight objects using just one sensor.
They found that they could quickly pick up and release flat objects, metal toys, cylinders, the double-curved part of a spoon, and an ultra-soft hydrogel ball.
After reconfiguring the sensor network to use all sensors for object detection, the gloves were also able to grip larger objects, such as a plate, box and bowl.
Flat, cylindrical, convex and spherical objects composed of both hard and soft materials were attached and lifted even when users did not grasp the object by closing their hands.
Postdoctoral researcher Ravi Tutika said: “These capabilities mimic the advanced manipulation, detection and control of cephalopods and provide a platform for synthetic underwater adhesive skins that can reliably manipulate diverse underwater objects,
“This is certainly a step in the right direction, but we still have a lot to learn about the octopus and how to make integrated adhesives before we reach the full gripping power of nature.”
In the future, the researchers hope the glove will play a role in underwater gripping robotics, user-assisted technologies, healthcare and wet object production.