Artificial muscle makes soft robots stronger

A new type of artificial muscle allows soft robots to lift nearly 1,000 times their own weight.

Scientists from Harvard University and MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) have created artificial muscles that allow soft robots to lift objects that are up to 1,000 times their own weight, a new study published in the Proceedings of the National Academy of Sciences reports.

Soft robotics has made large strides over the past decade. However, while recent advancements have enabled the machines to bend and flex in new ways, the softer materials typically come with reduced strength.

The new origami-inspired muscles in the study get around that obstacle and could one day lead to much more efficient machines.

“We were very surprised by how strong the actuators [aka, “muscles”] were,” said study co-author Daniela Rus, the Andrew and Erna Viterbi Professor of Electrical Engineering and Computer Science at MIT, according to Phys.org. “We expected they’d have a higher maximum functional weight than ordinary soft robots, but we didn’t expect a thousand-fold increase. It’s like giving these robots superpowers.”

Making muscle-like actuators is one of the largest challenges in engineering. Now that it has been overcome, scientists can potentially build nearly any robot for almost any task.

Each artificial muscle consists of an inner “skeleton” made from materials like metal coil or a sheet of folded plastic surrounded by air or fluid and sealed inside a plastic or textile bag. A vacuum inside the bag causes the muscles to move by forcing the “skin” to collapse onto the skeleton. That tension drives the motion, and allows the device to work without any other external human input. 

In the study, the team created dozens of different muscles with materials ranging from metal springs to packing foam to sheets of plastic. They then experimented with different skeleton shapes to create muscles that can contract down to 10 percent of their original size, lift a flower off the ground, and twist into a coil.

Those experiments showed the muscles can move in many ways, and are able to operate with a high amount of resilience. Not only that, but the technology can generate roughly six times more force per unit area than mammalian skeletal muscle, and is both lightweight and easy to make. A single muscle can be constructed within ten minutes using materials that cost less than $1.

Another important property is that the actuators are highly scalable, meaning they can be constructed at different sizes. That is important because it greatly increases their potential applications. The team believes they could one day be used for a wide variety of tasks, including miniature surgical devices, wearable robotic exoskeletons, transformable architecture, deep-sea manipulators, and large deployable structures for space exploration.

“The possibilities really are limitless,” added Rus, in a statement. “But the very next thing I would like to build with these muscles is an elephant robot with a trunk that can manipulate the world in ways that are as flexible and powerful as you see in real elephants.”

Strange sound waves discovered in quantum liquids

Physicists have theoretically shown that two types of sound waves can propagate in one-dimensional quantum fluids.

Standard sound waves, which are created by small oscillations of density, can propagate through all fluids and cause the liquid’s molecules to compress at repeating intervals. Now, a team of physicists from Argonne National Laboratory and at the University of Washington, Seattle have theoretically shown that two types of sound waves can propagate in one-dimensional quantum fluids.

“One-dimensional liquids have fascinating quantum properties that have been studied by physicists for decades,” said Konstantin Matveev, first author on the study. “Quite surprisingly, we have been able to show that even such an essentially classical phenomenon as sound is also very unusual in these liquids. Our work implies that even the simplest classical properties of a fluid can be strongly affected by its quantum nature.”

While classical fluids usually only support one kind of sound wave—a density wave—liquid helium as one exception. Since it’s a superfluid, it can travel without friction, allowing it to flow up and down the sides of its container.

And this is just one of its strange properties—unlike classical fluids, superfluid helium supports temperature waves and density waves, which propagate at differing velocities.

The team hopes to eventually experimentally demonstrate these hybrid sound waves through atomic traps or long quantum wires, where researchers know one-dimensional quantum liquids exist.

The findings were published in Physical Review Letters.

Shrimp-inspired camera could lead to new underwater technology

Researchers have used technology based off of mantis shrimp to create a new style of underwater GPS.

A new shrimp-inspired camera may help future technology see better underwater, according to new research published in the journal Science Advances.

This discovery comes from researchers at the University of Illinois, who took the expert underwater vision of the mantis shrimp and put it into a special camera. While humans cannot see well beneath the waves — mainly due to our thousands of years on land — many marine creatures can easily peer through the clear liquid.

The team in the study analyzed such creatures in order to understand which ones could see the best. That then led them to the mantis shrimp, which they used to create a brand new bio-inspired camera.

They chose the crustaceans because they can detect the polarization properties of underwater light. That means they are able to read how light refracts as it passes through water and bounces off of individual molecules. Using that as a baseline, the team managed to create a unique style of underwater GPS.

“We collected underwater polarization data from all over the world in our work with marine biologists and noticed that the polarization patterns of the water were constantly changing,” said study co-author Viktor Gruev, a professor at the University of Illinois, in a statement“This was in stark contrast to what biologists thought about underwater polarization information. They thought the patterns were a result of a camera malfunction, but we were pretty sure of our technology, so I knew this phenomenon warranted further investigation.”

In the study, scientists found that the underwater polarization patterns captured by the shrimp-like camera are linked to the sun’s position relative to the location where the recording was made. Using such information, researchers were able to estimate the sun’s heading and elevation angle. As a result, the team found they could calculate their coordinates by only knowing the date and time of filming.

Once they equipped the camera with an electronic compass and tilt sensor they were able to locate their position anywhere on Earth. Though the method is not as accurate at satellite reads, it is the best current GPS method for an underwater device.

Such information could one day help scientists locate missing aircraft or create detailed seafloor maps. There is even a chance it may allow biologists to track and study different marine species.

“Animals like turtles and eels, for example, probably use a slew of sensors to navigate their annual migration routes that take them thousands of miles across oceans,” added Gruev, according to ZME Science. “Those sensors may include a combination of magnetic, olfactory and possibly – as our research suggests – visual cues based on polarization information.”

New process could reveals mechanism behind smartphone battery fires

Scientists have discovered a process that could limit, and potentially end, overheating in smartphones

A group of researchers from Stanford University and the SLAC National Accelerator Laboratory may have discovered why smartphone batteries overheat and catch fire, according to a new research published in the journal Science.

In the study, the team used cryo-electron microscopy (cryo-EM) — a process where samples are flash-frozen in liquid nitrogen — to study lithium batteries. That then shed light on finger-like growths called dendrites, which can breach battery compartment barriers and cause both short circuits and fires.

The new process, which won the Nobel Prize in Chemistry this year, could give scientists a new way to look at molecules at the atomic scale, even when they are moving.

“This is super exciting and opens up amazing opportunities,” said lead author Yi Cui, a researcher from the National Accelerator Laboratory SLAC, in a statement. “With cryo-EM, you can look at a material that’s fragile and chemically unstable and you can preserve its pristine state – what it looks like in a real battery ­– and look at it under high resolution.”

To study these properties, the researchers looked at how lithium metal dendrites and their coatings reacted with various electrolytes. This showed that, while dendrites are crystalline when viewed at the atomic level, they form solid structures as they grow. In addition, scientists found that when they added a chemical known to improve performance to the coating, it became more orderly. That could then prevent dendrites and shut down potential overheating. 

This is the first time researchers have been able to study dendrites as they form. As a result, the information in the study could help stop overheating and create safer batteries in the future.

However, there is still a long way to go. While the study is a step in the right direction, many more trials need to be run on the new process. If that goes well, it could then lead to huge technological advancements, such as electric cars that can go weeks on a single charge.

“We were really excited. said study co-author Yanbin Li, a researcher at Stanford University, according to Science Alert. “This was the first time we were able to get such detailed images of a dendrite, and we also saw the nanostructure of the SEI layer for the first time. This tool can help us understand what different electrolytes do and why certain ones work better than others.”

Robotic “bees” are able dive in and out water, study reports

Researchers from Harvard have developed a robot that is able to both go underwater and come back out of the liquid without breaking.

A group of scientists from Harvard University have developed a robotic “bee” that can fly, swim underwater, and then move back up into the air.

The machine — which is apart of the latest generation of so-called RoboBees — is a big breakthrough. Not only can it do things past models were not capable of, but it is 1,000 times lighter than any previous aerial-to-aquatic robot.

“This is the first microrobot capable of repeatedly moving in and through complex environments,” explained lead author Yufeng Chen, a researcher at Harvard University, according to International Business Times. “We designed new mechanisms that allow the vehicle to directly transition from water to air, something that is beyond what nature can achieve in the insect world.”

While the new design is effective, creating a robot that can move in and out of water is not easy. That is because water is 1,000 times more dense than air, which means the machine need to flap their wings at different speeds depending on which medium they are in. If they flap too slowly they will not be able to fly, but if their wings move too fast they will break while submerged. 

In the study, the team used a combination of computer modelling and experimental data to get the robots to flap their wings between 9 and 13 hertz in water and 220 to 300 hertz in in the air.

Once that problem was solved, they next needed to design the machines in a way that would allow them to dive into water and bring themselves back out.

Past studies have shown that a powerful impact and sharp objects can help machines pierce through the surface of water. However, moving from the liquid — which has a surface tension that is more than 10 times the weight of the robot and three times its maximum lift — is a much more difficult process.

To overcome that, scientists fitted the RoboBee with four flotation devices and a special gas chamber filled with combustible fuel. The flotation devices first push the robot up to the surface so that its wings are out of water, and from there a spark ignites the gas to move it out the rest of the way. 

“Because the RoboBee has a limited payload capacity, it cannot carry its own fuel, so we had to come up with a creative solution to exploit resources from the environment,” said study co-author Elizabeth Helbling, a researcher at Harvard University, according to Tech Radar. “Surface tension is something that we have to overcome to get out of the water, but is also a tool that we can utilize during the gas collection process.”

This new design allows the devices to lift more than three times the amount of past models. That enables them to carry the gas chamber, the sparker, and buoyant outriggers. While they are still in early testing, the team hopes the machines will have a wide range of applications across different fields. Not only could they be used for search-and-rescue operations, but they could aid environmental monitoring and biological studies as well.

The study is outlined in the journal Science Robotics.

Liquid metal could help lead to faster electronics

Researchers have found a technique that creates extremely thin metal for use in electronics.

A team of researchers from RMIT University have uncovered a new technique to make atomically thin flakes of different materials, a process that could lead to faster, more efficient electronics.

In this method, certain metals are dissolved in liquid metal. Then, the resulting super-thin oxide layer is peeled off and can be used for various purposes. While it has not been extensively tested yet, the technique is predicted to work on roughly one-third of the periodic table.

As a proof of concept, scientists have used the method to create hafnium oxide with a thickness of just three atoms. That is roughly five to ten times thinner than hafnium oxide layers produced with other techniques. To get that thinness, researchers worked with the material for 18 long months.

“Here we found an extraordinary, yet very simple method to create atomically thin flakes of materials that don’t naturally exist as layered structures,” said study co-author Dr Torben Daeneke, a researcher at RMIT’s School of Engineering, according to Gizmodo Australia.

To do this, scientists use non-toxic alloys of gallium — a metal similar to aluminum — as a reaction medium to cover the surface of the liquid metal with atomically thin oxide layers of the added metal rather than the naturally occurring gallium oxide. Then, they exfoliate the oxide layer by touching the liquid metal with a smooth surface. Not only that but, as gallium alloy is liquid at room temperature, the process can be done safely at ambient conditions.

The new research is important because it could help scientists create semiconducting and dielectric components. Both of those are key for a lot of current technology. By making such components extremely thin, the team may be able to create stronger, more energy efficient electronics. The products could have applications in devices like batteries as well.

“The most important outcome of our work is that we introduce liquid metals as a reaction solvent which opens the door to a whole new type of chemistry,” added Daeneke, according to Yahoo News.

The recent findings are outlined in the journal Science.

Soft robotics draws inspiration from Octopus

Often scientists joke that it is as if it was dropped on this planet by some advanced alien species.

The octopus is one of the most advanced species on the planet. Often scientists joke that it is as if it was dropped on this planet by some advanced alien species. With over eight survival traits such as ink clouds and camouflage far superior to that of chameleons, it is easy to see why.

However, there is so much more scientists can learn from the octopus. One of them is how its muscular system works. Suffice to have eight powerful limps each able to pull almost ten times its weight, and the octopus muscles are also highly flexible. It is able to push its whole body through a keyhole.

Scientists in soft robotics have decided to use the principle of the Octopus muscular system to make significant progress in soft robotics. The “octobot” is made from silicon and liquid-gas muscles. Its locomotion depends on chemical reactions that push into limps.

At the moment it’s movement is highly irregular but still a big step forward. Prior soft robots still had hardware and were operated remotely. But the new version is entirely self-sufficient. “Many of the previous embodiments required tethers to external controllers or power sources,” said PhD student Ryan Truby from Harvard University. “What we’ve tried to do is actually to replace these hardware components entirely and have a completely soft robotic system.”

The scientist explains that he hopes that one day soft robot can do tasks that are humanly impossible even with hard robotics. They foresee a time when such robots can carry out internal surgery without significant insertions.