Tag Archives: soft robot

Soft robot hand can sweat to keep itself cool

Credit: Mishra et al, Science Robotics.

An experimental soft-bodied robotic hand maintains a stable temperature by releasing water through its tiny pores.

Although still a proof of concept, this bio-inspired approach could lead to a new class of robots that can operate for prolonged periods of time without overheating.

Sweaty robot palms

Robots and mechanical machines, in general, face important thermoregulation challenges, either because their components overheat or due to operating in hot environments like an assembly line or out in the field on a summer day. Cooling consumes a lot of energy, raising costs, while poor heat management can significantly impact the durability and performance of the machines.

Researchers at the Cornell University, Facebook Reality Labs, and the Center for Micro-BioRobotics in Pisa, addressed this challenge by looking at nature for a solution — the cooling power of perspiration naturally stood out.

“We believe [this] is a basic building block of a general purpose, adaptive, and enduring robot,” said Robert Shepherd, associate professor of Cornell’s Sibley School of Mechanical and Aerospace Engineering and co-author of the research,

When our bodies heat up, our millions of glands across our skin produce sweat — mostly water with a little bit of potassium, salt, and a few other minerals. Humans have the most efficient sweating system that we know of — we’re more of an exception in that we rely on secreting water on our skin to stay cool. Most furry mammals regulate their body temperature through panting while other animals like ectotherms — lizards, amphibians, and insects — have evolved other behaviors that help keep them cool.

Sweating enabled humans to march all day, even on hot summer days when most predators are out in the shade cooling off. So, in many ways, sweating has been a secret weapon that helped us survive and thrive across the world, in many different climates.

It makes sense to model some of our machines after this biological mechanism.

“It turns out that the ability to perspire is one of the most remarkable features of humans,” said Thomas Wallin, an engineer at Facebook Reality Labs and co-author of the new study. “We’re not the fastest animals, but early humans found success as persistent hunters. The combination of sweating, relative hairlessness, and an upright bipedal gait enabled us to physically exhaust our prey over prolonged chases.”

Credit: Science Robotics.

Wallin and colleagues designed a balloon-like robot fitted with pores that allow water to slowly ooze out — but only once the “body” temperature reaches a certain threshold. In order to make the hand-shaped robot respond to temperature, the researchers employed a hydrogel material called poly-N-isopropylacrylamide (PNIPAm). This material reacts to temperature passively, without the need for sensors or additional electronic components.

At 30 degrees Celsius (86 degrees Fahrenheit), the micropores in the soft robot’s top layer stay closed. Beyond this temperature, the pores expand, allowing pressurized fluid to leak — the robot sweats.

Experiments during which the robot was exposed to wind from a fan showed that the cooling rate was six times better than non-sweating machines. In fact, the thermoregulatory performance was even better than humans and horses (the other animal that sweats, although quite differently than humans do; horses still mainly rely on panting to cool off).

Such soft robots, however, aren’t well suited for all types of applications. The dripping solution makes the soft actuators slippery, making grasping challenging. The robot also runs out of water eventually and a refillable water tank isn’t always an option.

It’s still a very interesting proof of concept that shows you don’t need huge heat sinks and cooling fans to keep a robot’s temperature at optimal levels.

The findings appeared in the journal Science Robotics.

This robot passes through pipes to see where they’re leaking

Here’s a worrying thought: 20% of all the clean water produced in the world is wasted through water pipes. In the US alone, this amounts to 6 billion gallons of clean water, and although detection methods have advanced tremendously, most cracks are only discovered too late. But this robot might change it all.

Dr. You Wu holding the first working prototype of the robot in hand in 2017.

It might seem like a bit of overkill to develop a robot, then send it through pipes just to save some water. But when you consider the sheer scale of the problem, and how it’s essentially ubiquitous, the utility of the robot becomes much clearer. The soft robot you see above just netted the 2018 James Dyson Award, a design competition to celebrate up-and-coming inventors. Called Lighthouse, it was created by recent Massachusetts Institute of Technology (MIT) doctoral graduate You Wu. Wu wanted to design a soft, cheap bot that would tackle the massive and global problem of water waste.

Lighthouse is inserted through a waterway using an existing hydrant, where it passively navigates through the pipe. Whenever there’s a pipe, it generates a suction force, and the robot measures the strength of the suction, also recording its location. After the robot is flushed out, a surveyor can come and download a map of any potential leaks. Based on this map, reparations can be planned and carried out — but more importantly, preventive measures could be taken.

Herein lies the great advantage of robots like Lighthouse: it allows the detection of leaks before they get to do major damage, which could end up saving a lot of water — and a lot of money. Lighthouse can reportedly discover leaks that are as small as a 4-millimeter crack, which loses just one gallon of water per minute — that’s five times less than a regular shower.

Ultimately, water is a finite resource, and we’re not taking particularly good care of it right now. We’re wasting much of it, and as a result, many people around the world are already facing acute shortage issues. While Lighthouse won’t single-handedly solve that, it has the potential to make a dent, and be a piece of a much-needed solution.

“Every year, there are 240,000 water pipe breaks in the US, and many of them cause sinkholes and other severe damage to the infrastructure. Water utilities need methods for detecting and locating such leaks before they become big breaks, so that they can perform preventative maintenance to save water and protect infrastructure. If we can find and fix half of all leaks in the world, we can recover enough leaked water to support 1 billion more people’s daily need,” the producer’s webpage reads.

New “soft robots” are strong enough to lift heavy weights, delicate enough to pluck a raspberry

Scientists have already developed strong, capable robots. The next step is creating delicate, nimble robots — and that’s exactly what Colorado researchers have accomplished. They’ve outfitted robots with muscle-like features, offering them not only the power to manipulate heavy objects but also the gentleness to do so without damaging them.

Credits: Keplinger Research Group.

Already, robots are being used in a myriad of industries, mostly for repetitive tasks which require a lot of power. But, they’re typically rigid and apply a fixed amount of force. Meanwhile, gentler robots and robots which can apply varying force can also be useful in a number of tasks, from picking fruit to helping elderly or impaired people. So scientists from the University of Colorado in Boulder wanted to explore the softer side of these machines.

“We want to do the opposite,” said Christoph Keplinger, assistant professor in CU’s Department of Mechanical Engineering. “We want robots who will be our friends and help us.”

They sought inspiration from biology, focusing on two technologies:

Pneumatic actuators are powerful and relatively easy to fabricate, but they can be bulky and their movements tend to be rigid. Meanwhile, dielectric elastomer actuators are much faster and smoother, but they’re more prone to failure. Keplinger and his colleagues joined the two technologies in an innovative project — it’s like mixing the strength of an elephant with the delicacy of a hummingbird, they say.

“Think about a hummingbird and the high speed of its wings,” Keplinger said. “Then think about the power of the trunk of an elephant. At the same time, think about an octopus arm, which is extremely versatile and can squeeze through tiny spaces.”

Nick Kellaris, a materials science and engineering graduate student, left, and mechanical engineering graduate student Eric Acome look over liquified artificial “muscle” or soft robot material in the Keplinger Research Lab. Photo by Glenn Asakawa / University of Colorado Boulder.

This field of research is called “soft robotics” and their project is named “hydraulically amplified self-healing electrostatic” — or HASEL. HASEL eschews the traditional idea of a metallic droid, replacing it with a soft shell capable of mimicking the expansion and contraction of biological muscles. To make things even better, this robot can not only be built from cheap, readily available materials, but it’s also self-repairing.

Basically, the donut-shaped elastomer shell is filled with an insulating liquid (such as canola oil). It’s then hooked to a pair of electrodes and, when a voltage is applied, the liquid is displaced, shifting the shape of the soft shell. When the voltage is turned off or reduced, the grip is released. In terms of general physics, it works very much like a biological muscle. Through sensors, HASEL can also pick up environmental cues, making it even more lifelike.

“We draw our inspiration from the astonishing capabilities of biological muscle,” said Christoph Keplinger, senior author of both papers, an assistant professor in the Department of Mechanical Engineering and a fellow of the Materials Science and Engineering Program.“HASEL actuators synergize the strengths of soft fluidic and soft electrostatic actuators, and thus combine versatility and performance like no other artificial muscle before.

Keplinger details his project in a pair of papers published in Science and Science Reports. They built three designs, and to show them off, they had the robots complete tasks which require both strength and tenderness. For instance, the robots were able to lift heavy weights, but they were also able to handle delicate objects such as a raspberry and a raw egg.

Eric Acome, lead author of the Science paper, and Nick Kellaris, lead author of the Science Robotics paper, say that they have high hopes for their design.

“We can make these devices for around 10 cents, even now,” said Nicholas Kellaris, also a doctoral student in the Keplinger group and the lead author of the Science Robotics study. “The materials are low-cost, scalable and compatible with current industrial manufacturing techniques.”

A muscle-like electrical actuator developed by researchers in the Keplinger lab. Photo by Glenn Asakawa/University of Colorado Boulder.

Robert Shepherd, a soft robotics expert at Cornell University, who was not involved in the study, told ScienceMag that this is a very big step forward, while Bobby Braun, dean of CU Boulder’s College of Engineering and Applied Science said that the research is “nothing short of astounding.”

Considering the performance, low price, and versatility of these robots, we could expect them to make a real impact on society in the near future.

“We’d like to do this as soon as possible to start making an impact on people’s lives,” Keplinger concludes.

Softbot navigating maze.

Plant-like robot can grow 250 times its length, manipulate objects, form complex shapes

A new soft robot designed by researchers from the University of California, Santa Barbara can ‘grow’ like a plant — only much faster.

Softbot navigating maze.

Image credits Elliot W. Hawkes et al., 2017.

A team from Stanford Uni and the University of California, led by Elliot Hawkes of UoC’s Department of Mechanical Engineering designed and build a prototype soft-robot that can grow to explore its environments, akin to a vine of fungus. The design could help create a new class of robots which can traverse cramped or otherwise constrained environments.

The robot’s mechanical body is housed inside a plastic tube reel. The tube can be pneumatically extended, in a manner similar to how some invertebrates (such as Sipunculus nudus, the peanut worm) move around.

The plastic tube also allows the robot to change direction — one component handles the inflating process, while another allows the whole thing to shift direction. To see when it’s about to run into something, the robot also comes equipped with a nose-mounted camera.

Overall, the robot can extend up to 72 meters in length, at a speed of 10 meters per second. As a proof-of-concept of their prototype bot, Hawkes’ team had it crawl through flypaper, glue, even over a bed of nails.

They even programmed it to form various 3-D structures (such as a radio antenna), used it to turn off a valve, and had it act as a fire extinguisher.

A paper describing the robot, titled “A soft robot that navigates its environment through growth,” has been published in the journal Science Robotics.

All images and video credits to Image credits Elliot W. Hawkes et al., 2017, Science Robotics.

New soft heart robot could save many lives from heart failure

A soft, customizable robot fits around a human heart and helps it beat. Without actually touching any blood, it augments cardiovascular functions, reducing the risk of clots and eliminating the need for dangerous blood thinning medication. All this sounds like Science Fiction — but it’s very much real. The technology was developed by researchers from Harvard University and Boston Children’s Hospital as a treatment for people suffering from heart failure.

In vivo demonstration of cardiac assist in a porcine model of acute heart failure (Video courtesy of Ellen Roche/Harvard SEAS)
Credit: Courtesy of Ellen Roche/Harvard SEAS

Heart failure affects over 40 million people every year. Today, we have some possibilities to mechanically aid the heart through pumps called ventricular assist devices (VADs) which pump blood from the ventricles into the aorta, and heart transplant. While this is spectacular in itself, patients using VADs are still at risk of blood clots and stroke, so scientists wanted a different option, a robot which isn’t in contact with any blood.

“This work represents an exciting proof of concept result for this soft robot, demonstrating that it can safely interact with soft tissue and lead to improvements in cardiac function. We envision many other future applications where such devices can delivery mechanotherapy both inside and outside of the body,” said Conor Walsh, senior author of the paper and the John L. Loeb Associate Professor of Engineering and Applied Sciences at SEAS and Core Faculty Member at the Wyss Institute.

To create the device, they took inspiration from the heart itself. It features soft pneumatic actuators placed around the heart, mimicking the outer muscle layers of the mammalian heart. They’re covered with a thin silicone sleeve, and the actuators pull and compress the sleeve in a similar fashion to a real heart. Everything is connected to an external pump which uses air to power the actuators. In other words, it stimulates the heart just like the real muscles do, but from the outside – not from within.

Researchers have really big plans for this technology, and soft robots seem like a great fit for this type of invasive yet delicate interventions.

“This work represents an exciting proof of concept result for this soft robot, demonstrating that it can safely interact with soft tissue and lead to improvements in cardiac function. We envision many other future applications where such devices can delivery mechanotherapy both inside and outside of the body,” said Conor Walsh, senior author of the paper and the John L. Loeb Associate Professor of Engineering and Applied Sciences at SEAS and Core Faculty Member at the Wyss Institute.

So far, the work has only been tested in a lab and on animal models — there’s still a way to go before it will be tested on humans. But the research opens intriguing possibilities: can we truly augment human organs with soft, external robots? The answer will likely be ‘yes.’

Scientists develop new, adorable class of soft robots

Harvard researchers have revealed a cute, self-powered octopus-like robot. The robot is surprisingly resilient and can operate for up to eight minutes by itself, opening up new possibilities in robot design.

 This image shows the octobot, an entirely soft, autonomous robot. A pneumatic network (red) is embedded within the octobot’s body and hyperelastic actuator arms (blue). Credit: Ryan Truby, Michael Wehner, and Lori Sanders, Harvard University.

This image shows the Octobot, an entirely soft, autonomous robot. A pneumatic network (pink) is embedded within the Octobot’s body and hyperelastic actuator arms (light blue). Credit: Ryan Truby, Michael Wehner, and Lori Sanders, Harvard University.

Soft robots could revolutionize the industry. They’re more adaptable to many natural environments, and are ironically more resilient than their solid counterparts because they can adapt to various environments. However, there are some very big hurdles against soft robots – especially batteries.

“Soft robots possess many attributes that are difficult, if not impossible, to achieve with conventional robots composed of rigid materials,” researchers write in the study. “Yet, despite recent advances, soft robots must still be tethered to hard robotic control systems and power sources.”

You can’t really fit conventional batteries on a soft robot… because batteries are hard. So, the big challenge is making these squishy bots fully autonomous — something  Jennifer Lewis and her colleagues at Harvard University managed to overcome, and created the cute ‘octobot’ you see above.

“Creating a new class of fully soft, autonomous robots is a grand challenge, because it requires soft analogues of the control and power hardware currently used,” Lewis added in the study.

They used a combination of techniques to develop it, including 3D printing of the pneumatic networks within the soft body. Octobot can operate autonomously for 4-8 minutes, but that run-time could be significantly improved by a more sophisticated design of fuel usage.

Like with any nascent technology, there are no immediate applications in sight, but in the long run, soft robots could really be a game changer. Speaking with ZME Science, Ryan Truby, author and Ph.D. candidate at Harvard University’s Paulson School of Engineering and Applied Sciences discussed potential applications for the technology:

“Soft robotics is definitely a field in its infancy,” he said. “The potential applications that are particularly exciting for soft robotic systems are those that sit at the human interface, such as wearable and biomedical technologies. Because these robotic systems are based on soft materials like silicone rubbers, they can be inherently safer than traditional robotic systems and possibly better suited for such applications. Additionally, we are finding that soft robots have potential application in environments where conventional robots might fail, such as underwater conditions. “

Michael Wehner, the co-lead author on the paper added:

“As Ryan points out, this is a new field so the “Killer App” is yet to be determined. Some early avenues to explore are in fields involving human-robot-interaction, a long-time focus area of mine.”

“As inherently soft, soft robots pose less risk to both humans and the robots themselves in unplanned interactions, which must be accounted for in unstructured environments.”

Another interesting point about the robot is its fuel. The Octobot system uses concentrated hydrogen peroxide as fuel, which is already a pretty eco-friendly option, the byproducts being oxygen, water and heat. The hydrogen peroxide decomposes into oxygen gas and water vapor, as regulated by the microfluidic “soft controller,” powering actuation. This approach also opens up an intriguing possibility, as Truby explains:

“I think that in the future, it would be neat to see if a robot like the Octobot could possess the ability to produce hydrogen peroxide on-board using reagents from its environment. This could be done, for example, using a biochemical reaction that is regulated within the soft robot. However, this would be a tremendous challenge!”

Journal Reference: An integrated design and fabrication strategy for entirely soft, autonomous robots.

octopus arm robot

The squishy bot revolution: how soft robotics is changing the field

When people think of robots, the image of a helpful anthropocentric bot is conjured, like Rosie from The Jetsons or 3CPO from Star Wars. In the 21st century, robots are already ubiquitous, but not the kind you imagine. Thousands of meticulous, stern robots dot any modern assembly line. With precise motion and blazing speed, these robots assemble the nanometer transistors stacked by the millions inside your iPhone’s CPU or fix nuts and bolts in a Tesla Model S. For the past decade or so, a great deal of interest has been shown in a novel class of robots. It’s called soft robotics, and involves machines designed to resemble biological systems like squids, caterpillars, starfish, human hands and more. Though far less practical at this point, soft robots could prove invaluable soon enough.

A different kind of software

Hard robots, made of rigid limbs, involve very meticulous programming. These machines ‘know’ very well what they need to do, and complete the task. If there’s a problem, it’s the programmer’s/developer’s fault. The problem is that these become useless once you put them outside of their environment. Soft robots, on the other hand, are made from elastic and flexible materials which allow them to mold to the environment, just like the biological counterparts. Such machines can stretch, twist, scrunch and squish, change shape or size, wrap around objects and perform tasks impossible by rigid robotics standards.

octopus arm robot


A prime example is an octopus-like bot developed at the Sant’Anna School of Advanced Studies in Pisa, Italy which aims to improve surgical operations. Just like its aquatic inspiration, the Stiff-Flop robotic tentacle has no rigid skeleton. Instead, movements are driven by inflatable compartments, while its stiffness is held by a tube filled with coffee.

“The human body represents a highly challenging and non-structured environment, where the capabilities of the octopus can provide several advantages with respect to traditional surgical tools,” said the paper’s lead author Tommaso Ranzani, from the Sant’Anna School of Advanced Studies in Pisa.

Traditionally, surgical tasks involve a myriad of special instruments from graspers, to dissectors, to retractors. The Italian researchers hope that eventually, their soft-bodied robot will use its tentacles to  find a way through an awkward area, then hold together a delicate organ with one arm, while another performs surgery. The number of instruments and operations required would be significantly trimmed.

The current prototype is 14cm long and 3cm across and split into two sections. And while it still has a long way to go before you let this thing anywhere near your guts, it is a great proof of concept of what’s to come.

A soft cube that jumps using a steel tongue. MIT

A soft cube that jumps using a steel tongue. MIT

At MIT’s Computer Science and Artificial Intelligence Lab (CSAIL), researchers built a 3-inch cube. Sensors track its position, and this information is used by the squishy bot to deploy steel ‘tongues’ to move about.  The bendable steel presses against whatever surface the cube is resting on, propelling it up with a jump. Future versions might become equipped with a camera so the jumping cube can be used in disaster relief situation.


squishy robot

Harvard University made a robot that mixes the blending capabilities of a squid with the locomotion mechanics of a sea creature. The robot employs a dynamic coloring system, based on micro-channels into which dye is pumped. These color layers used for the camouflage were first created using molds from 3D printers. Silicone is then poured into the molds to create these micro-channels, topped with another layer of silicone. In all, it takes 30 seconds for the robot to fill with color and another 30 seconds for it to drain – a full minute to completely blend into its surroundings or, oppositely, stand out.

robot run over car

A flexible body, the robot moves like a flailing starfish over all terrain. Credit: Harvard University.

Made of mostly silicon, this X-shaped soft robot uses a pneumatic network embedded inside to move about. It’s controlled by a simple Arduino board, while a GoPro acts as a visual sensor. According to the Harvard researchers who devised it, the robot can squirm over fire, across ice, and survive under a car tire.

MIT robot design

Though usually the domain of rigid robots, there are instances where a soft robot can become useful in manufacturing. Imagine a busy Amazon warehouse where robots are regularly used to stack, retrieve items or clean up. There’s a different robot for each function, and each robot uses a distinct feature in its own turn. An MIT design uses sensors in the hand that can measure the shape of the object, using an algorithm that allows the hand to distinguish one object from others. It can recognize a variety of different objects: a CD, an egg or a cup, for instance. Much more versatile.

“The idea with a soft hand is that it’s a lot easier for the robot to pick something up,” said Bianca Homberg, a graduate student in MIT’s Distributed Robotics Lab, and the lead researcher on the project.

“With a rigid hand,” Homberg added, “there has to be a lot of complicated grasp planning to figure out how exactly it is going to pick up the object — where it is going to put its fingers so that it doesn’t drop [the object]. With a soft hand you just grab it and the fingers bend around the object and pick it up.”


Versaball playing beer pong.

Versaball playing beer pong.

Versaball playing beer pong.

Soft robots for gripping are being tested in many other places, elsewhere. Created in a collaboration between the University of Chicago and Cornell University, this gripper is called the Versabal. It utilizes the “jamming transition” phenomenon, in which granular objects remain loose and almost liquid ordinarily, but jam together to form a solid when vacuum-packed.

It’s basically a really, really effective air suction cup. By applying vacuum inside the ball, the Versaball can pick up an object by wrapping around it. Simply by releasing the vacuum, the object is released.

Though all these contraptions might look squishy and useless, they’re not. A lot of surprises will follow in the coming years. The soft-bot revolution is waiting to happen.