Nav: Home

Robotic 'gray goo'

March 20, 2019

New York, NY--March 20, 2019--The concept of "gray goo," a robot comprised of billions of nanoparticles, has fascinated science fiction fans for decades. But most researchers have dismissed it as just a wild theory.

Current robots are usually self-contained entities made of interdependent subcomponents, each with a specific function. If one part fails, the robot stops working. In robotic swarms, each robot is an independently functioning machine.

In a new study published today in Nature, researchers at Columbia Engineering and MIT Computer Science & Artificial Intelligence Lab (CSAIL), demonstrate for the first time a way to make a robot composed of many loosely coupled components, or "particles." Unlike swarm or modular robots, each component is simple, and has no individual address or identity. In their system, which the researchers call a "particle robot," each particle can perform only uniform volumetric oscillations (slightly expanding and contracting), but cannot move independently.

The team, led by Hod Lipson, professor of mechanical engineering at Columbia Engineering, and CSAIL Director Daniela Rus, discovered that when they grouped thousands of these particles together in a "sticky" cluster and made them oscillate in reaction to a light source, the entire particle robot slowly began to move forward, towards the light.

"You can think of our new robot as the proverbial "Gray Goo," says Lipson. "Our robot has no single point of failure and no centralized control. It's still fairly primitive, but now we know that this fundamental robot paradigm is actually possible. We think it may even explain how groups of cells can move together, even though individual cells cannot."

Researchers have been building autonomous robots for more than a century, but these have been non-biological machines that cannot grow, heal, or recover from damage. The Columbia Engineering/MIT team has been focused on developing robust, scalable robots that can function even when individual components fail.

"We've been trying to fundamentally rethink our approach to robotics, to discover if there is a way to make robots differently," says Lipson who directs the Creative Machines lab. "Not just make a robot look like a biological creature but actually construct it like a biological system, to create something that is vast in complexity and abilities yet composed of fundamentally simple parts."

Rus, who is also the Andrew (1956) and Erna Viterbi Professor of Electrical Engineering and Computer Science at MIT, adds, "All creatures in nature are made of cells that combine in different ways to make organisms. In developing particle robots, the question we ask is, can we have robotic cells that can be composed in different ways to make different robots? The robot could have the best shape required by the task--a snake to crawl through a tunnel or a three-handed machine for a factory floor. We could even give these particle robots the ability to make themselves. Suppose, for example, that a robot needs a screw driver from the table--the screw driver is too far to reach. What if the robot could reshuffle its cells to grow an extra long arm? As its goals change, its body can change too."

The team, working with Chuck Hoberman at Harvard's Wyss Institute and other researchers at Cornell, used many identical components, or particles, that could perform a simple motion like expansion and contraction. In simulations, they demonstrated robots comprising 100,000 particles. Experimentally, they demonstrated a system comprising two dozen particles.

"The particles closer to the light source experience brighter light and thus start their cycle earlier," explains Shuguang Li, co-first author of the paper who conducted the physical experiments. Li, who was a postdoctoral fellow in Lipson's former lab at Cornell and is currently a postdoc with Rus at CSAIL, continues. "That movement creates a sort of wave throughout the cluster, from the ones closer to the light to the ones further away, and that wave makes the entire cluster move towards the light. The movement toward light creates a global motion, even though the individual particles cannot move independently."

Modeling this behavior in simulations, they explored obstacle avoidance and object transport at greater scales, with hundreds and thousands of particles. They were also able to demonstrate the resilience of their particle robot paradigm both to noisy components and to individual failure.

"We found that our particle robots maintained approximately half of their fully functioning speed even when 20 percent of the particles are dead," says Richa Batra, co-first author of the paper and Lipson's PhD student who led the simulation studies.

The team is already testing their system with a larger number of cm-scale particles. They are also exploring other forms of particle robots, such as vibrating microspeheres.

"We think it will be possible one day to make these kinds of robots from millions of tiny particles, like microbeads that respond to sound or light or chemical gradient," says Lipson. "Such robots could be used to do things like clean up areas or explore unknown terrains/structures."
-end-
About the Study

The study is titled "Particle robotics based on statistical mechanics of loosely-coupled components."

Authors are: Shuguang Li 1, 2; Richa Batra 2; David Brown 3; Hyun-Dong Chang 3; Nikhil Ranganathan 3; Chuck Hoberman 4,5; Daniela Rus 1; Hod Lipson 2
1 Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology
2 Creative Machines Laboratory, Mechanical Engineering Department, Columbia Engineering
3 School of Mechanical and Aerospace Engineering, Cornell University
4 Graduate School of Design, Harvard University
5 Wyss Institute for Biologically Inspired Engineering, Harvard University

This work was supported in part by the Defense Advanced Research Projects Agency (grant number: HR0011-17-2-0014), and the National Science Foundation (grant number: 1138967 and 1830901).

The authors declare no financial or other conflicts of interest.

Media contacts:
Columbia Engineering:
Holly Evarts, Director of Strategic Communications and Media Relations
212-854-3206 (o), 347-453-7408 (c), holly.evarts@columbia.edu

MIT
Abby Abazorius, MIT News Office
abbya@mit.edu; 617-253-2709

LINKS:

Paper: https://www.nature.com/articles/s41586-019-1022-9
DOI: 10.1038/s41586-019-1022-9
http://engineering.columbia.edu/
https://www.nature.com/
https://engineering.columbia.edu/faculty/hod-lipson
https://www.csail.mit.edu/
http://danielarus.csail.mit.edu/


https://wyss.harvard.edu/team/associate-faculty/chuck-hoberman/Columbia Engineering

Columbia Engineering, based in New York City, is one of the top engineering schools in the U.S. and one of the oldest in the nation. Also known as The Fu Foundation School of Engineering and Applied Science, the School expands knowledge and advances technology through the pioneering research of its more than 220 faculty, while educating undergraduate and graduate students in a collaborative environment to become leaders informed by a firm foundation in engineering. The School's faculty are at the center of the University's cross-disciplinary research, contributing to the Data Science Institute, Earth Institute, Zuckerman Mind Brain Behavior Institute, Precision Medicine Initiative, and the Columbia Nano Initiative. Guided by its strategic vision, "Columbia Engineering for Humanity," the School aims to translate ideas into innovations that foster a sustainable, healthy, secure, connected, and creative humanity.

Columbia University School of Engineering and Applied Science

Related Robots Articles:

Darn you, R2! When can we blame robots?
A recent study finds that people are likely to blame robots for workplace accidents, but only if they believe the robots are autonomous.
Robots need a new philosophy to get a grip
Robots need to know the reason why they are doing a job if they are to effectively and safely work alongside people in the near future.
How can robots land like birds?
Birds can perch on a wide variety of surfaces, thick or thin, rough or slick.
Soft robots for all
Each year, soft robots gain new abilities. They can jump, squirm, and grip.
Robots activated by water may be the next frontier
Columbia University scientists have developed material that can drive mechanical systems, with movements controlled by a pattern set into the design.
The robots that dementia caregivers want: robots for joy, robots for sorrow
A team of scientists spent six months co-designing robots with informal caregivers for people with dementia, such as family members.
Faster robots demoralize co-workers
A Cornell University-led team has found that when robots are beating humans in contests for cash prizes, people consider themselves less competent and expend slightly less effort -- and they tend to dislike the robots.
Increasing skepticism against robots
In Europe, people are more reserved regarding robots than they were five years ago.
Humans help robots learn tasks
With a smartphone and a browser, people worldwide will be able to interact with a robot to speed the process of teaching robots how to do basic tasks.
Robots as tools and partners in rehabilitation
Why trust should play a crucial part in the development of intelligent machines for medical therapies.
More Robots News and Robots Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

Risk
Why do we revere risk-takers, even when their actions terrify us? Why are some better at taking risks than others? This hour, TED speakers explore the alluring, dangerous, and calculated sides of risk. Guests include professional rock climber Alex Honnold, economist Mariana Mazzucato, psychology researcher Kashfia Rahman, structural engineer and bridge designer Ian Firth, and risk intelligence expert Dylan Evans.
Now Playing: Science for the People

#541 Wayfinding
These days when we want to know where we are or how to get where we want to go, most of us will pull out a smart phone with a built-in GPS and map app. Some of us old timers might still use an old school paper map from time to time. But we didn't always used to lean so heavily on maps and technology, and in some remote places of the world some people still navigate and wayfind their way without the aid of these tools... and in some cases do better without them. This week, host Rachelle Saunders...
Now Playing: Radiolab

Dolly Parton's America: Neon Moss
Today on Radiolab, we're bringing you the fourth episode of Jad's special series, Dolly Parton's America. In this episode, Jad goes back up the mountain to visit Dolly's actual Tennessee mountain home, where she tells stories about her first trips out of the holler. Back on the mountaintop, standing under the rain by the Little Pigeon River, the trip triggers memories of Jad's first visit to his father's childhood home, and opens the gateway to dizzying stories of music and migration. Support Radiolab today at Radiolab.org/donate.