Nav: Home

Flexible yet sturdy robot is designed to 'grow' like a plant

November 07, 2019

In today's factories and warehouses, it's not uncommon to see robots whizzing about, shuttling items or tools from one station to another. For the most part, robots navigate pretty easily across open layouts. But they have a much harder time winding through narrow spaces to carry out tasks such as reaching for a product at the back of a cluttered shelf, or snaking around a car's engine parts to unscrew an oil cap.

Now MIT engineers have developed a robot designed to extend a chain-like appendage flexible enough to twist and turn in any necessary configuration, yet rigid enough to support heavy loads or apply torque to assemble parts in tight spaces. When the task is complete, the robot can retract the appendage and extend it again, at a different length and shape, to suit the next task.

The appendage design is inspired by the way plants grow, which involves the transport of nutrients, in a fluidized form, up to the plant's tip. There, they are converted into solid material to produce, bit by bit, a supportive stem.

Likewise, the robot consists of a "growing point," or gearbox, that pulls a loose chain of interlocking blocks into the box. Gears in the box then lock the chain units together and feed the chain out, unit by unit, as a rigid appendage.

The researchers presented the plant-inspired "growing robot" this week at the IEEE International Conference on Intelligent Robots and Systems (IROS) in Macau. They envision that grippers, cameras, and other sensors could be mounted onto the robot's gearbox, enabling it to meander through an aircraft's propulsion system and tighten a loose screw, or to reach into a shelf and grab a product without disturbing the organization of surrounding inventory, among other tasks.

"Think about changing the oil in your car," says Harry Asada, professor of mechanical engineering at MIT. "After you open the engine roof, you have to be flexible enough to make sharp turns, left and right, to get to the oil filter, and then you have to be strong enough to twist the oil filter cap to remove it."

"Now we have a robot that can potentially accomplish such tasks," says Tongxi Yan, a former graduate student in Asada's lab, who led the work. "It can grow, retract, and grow again to a different shape, to adapt to its environment."

The team also includes MIT graduate student Emily Kamienski and visiting scholar Seiichi Teshigawara, who presented the results at the conference.

The last foot

The design of the new robot is an offshoot of Asada's work in addressing the "last one-foot problem" -- an engineering term referring to the last step, or foot, of a robot's task or exploratory mission. While a robot may spend most of its time traversing open space, the last foot of its mission may involve more nimble navigation through tighter, more complex spaces to complete a task.

Engineers have devised various concepts and prototypes to address the last one-foot problem, including robots made from soft, balloon-like materials that grow like vines to squeeze through narrow crevices. But Asada says such soft extendable robots aren't sturdy enough to support "end effectors," or add-ons such as grippers, cameras, and other sensors that would be necessary in carrying out a task, once the robot has wormed its way to its destination.

"Our solution is not actually soft, but a clever use of rigid materials," says Asada, who is the Ford Foundation Professor of Engineering.

Chain links

Once the team defined the general functional elements of plant growth, they looked to mimic this in a general sense, in an extendable robot.

"The realization of the robot is totally different from a real plant, but it exhibits the same kind of functionality, at a certain abstract level," Asada says.

The researchers designed a gearbox to represent the robot's "growing tip," akin to the bud of a plant, where, as more nutrients flow up to the site, the tip feeds out more rigid stem. Within the box, they fit a system of gears and motors, which works to pull up a fluidized material -- in this case, a bendy sequence of 3-D-printed plastic units interlocked with each other, similar to a bicycle chain.

As the chain is fed into the box, it turns around a winch, which feeds it through a second set of motors programmed to lock certain units in the chain to their neighboring units, creating a rigid appendage as it is fed out of the box.

The researchers can program the robot to lock certain units together while leaving others unlocked, to form specific shapes, or to "grow" in certain directions. In experiments, they were able to program the robot to turn around an obstacle as it extended or grew out from its base.

"It can be locked in different places to be curved in different ways, and have a wide range of motions," Yan says.

When the chain is locked and rigid, it is strong enough to support a heavy, one-pound weight. If a gripper were attached to the robot's growing tip, or gearbox, the researchers say the robot could potentially grow long enough to meander through a narrow space, then apply enough torque to loosen a bolt or unscrew a cap.

Auto maintenance is a good example of tasks the robot could assist with, according to Kamienski. "The space under the hood is relatively open, but it's that last bit where you have to navigate around an engine block or something to get to the oil filter, that a fixed arm wouldn't be able to navigate around. This robot could do something like that."
-end-
This research was funded, in part, by NSK Ltd.

Written by Jennifer Chu, MIT News Office

Related links

Video: https://www.youtube.com/watch?v=Rnwx2zHGvIg&feature=youtu.be

Underwater robot for port security

http://news.mit.edu/2014/underwater-robot-for-port-security-0926

Getting a grip on robotic grasp

http://news.mit.edu/2014/getting-grip-robotic-grasp-0718

Researchers engineer light-activated skeletal muscle

http://news.mit.edu/2012/mechanical-engineers-create-light-activated-skeletal-muscle-0830

Inside the innards of a nuclear reactor

http://news.mit.edu/2011/nuclear-robots-0721

Massachusetts Institute of Technology

Related Engineering Articles:

Engineering the meniscus
Damage to the meniscus is common, but there remains an unmet need for improved restorative therapies that can overcome poor healing in the avascular regions.
Artificially engineering the intestine
Short bowel syndrome is a debilitating condition with few treatment options, and these treatments have limited efficacy.
Reverse engineering the fireworks of life
An interdisciplinary team of Princeton researchers has successfully reverse engineered the components and sequence of events that lead to microtubule branching.
New method for engineering metabolic pathways
Two approaches provide a faster way to create enzymes and analyze their reactions, leading to the design of more complex molecules.
Engineering for high-speed devices
A research team from the University of Delaware has developed cutting-edge technology for photonics devices that could enable faster communications between phones and computers.
Breakthrough in blood vessel engineering
Growing functional blood vessel networks is no easy task. Previously, other groups have made networks that span millimeters in size.
Next-gen batteries possible with new engineering approach
Dramatically longer-lasting, faster-charging and safer lithium metal batteries may be possible, according to Penn State research, recently published in Nature Energy.
What can snakes teach us about engineering friction?
If you want to know how to make a sneaker with better traction, just ask a snake.
Engineering a plastic-eating enzyme
Scientists have engineered an enzyme which can digest some of our most commonly polluting plastics, providing a potential solution to one of the world's biggest environmental problems.
A new way to do metabolic engineering
University of Illinois researchers have created a novel metabolic engineering method that combines transcriptional activation, transcriptional interference, and gene deletion, and executes them simultaneously, making the process faster and easier.
More Engineering News and Engineering Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Teaching For Better Humans 2.0
More than test scores or good grades–what do kids need for the future? This hour, TED speakers explore how to help children grow into better humans, both during and after this time of crisis. Guests include educators Richard Culatta and Liz Kleinrock, psychologist Thomas Curran, and writer Jacqueline Woodson.
Now Playing: Science for the People

#556 The Power of Friendship
It's 2020 and times are tough. Maybe some of us are learning about social distancing the hard way. Maybe we just are all a little anxious. No matter what, we could probably use a friend. But what is a friend, exactly? And why do we need them so much? This week host Bethany Brookshire speaks with Lydia Denworth, author of the new book "Friendship: The Evolution, Biology, and Extraordinary Power of Life's Fundamental Bond". This episode is hosted by Bethany Brookshire, science writer from Science News.
Now Playing: Radiolab

Space
One of the most consistent questions we get at the show is from parents who want to know which episodes are kid-friendly and which aren't. So today, we're releasing a separate feed, Radiolab for Kids. To kick it off, we're rerunning an all-time favorite episode: Space. In the 60's, space exploration was an American obsession. This hour, we chart the path from romance to increasing cynicism. We begin with Ann Druyan, widow of Carl Sagan, with a story about the Voyager expedition, true love, and a golden record that travels through space. And astrophysicist Neil de Grasse Tyson explains the Coepernican Principle, and just how insignificant we are. Support Radiolab today at Radiolab.org/donate.