Self-Replicating Robots

ABC News is running a story that self-replicating robots are no longer the stuff of science fiction. Scientists at Cornell University have created small robots that can build copies of themselves. Here is a movie demonstrating the self-replication process. And the paper that will be published in Thursdays issue of Nature.

Not replication

[pmazer]

That's a really cool robot and all, but it's not replicating itself. It's just taking more pieces, already machined, of itself to break itself in two.

Re:Not replication

[r4bb1t]

This type of "replication" is what Von Neumann envisioned with his kinetic automata. They essentially sit in a sea of their own parts and use them to reproduce themselves. It started the field of cellular automata [wikipedia.org] that is used today in biology and elsewhere. It may not seem like much, but it's a promising first step.

Re:Video is really slow

[mark-t]

This could be done, if web browsers themselves would effectively function as mirrors for a site for as long as the person using that browser stays on that site. Operating somewhat like a torrent, the first visitor to a site would essentially act as a seed, and then future visitors would receive the IP's of other visitors to the same page, and they would download the page contents from eachother. As the number of visitors drops, the original server could be more readily able to handle seeding other visitors.

Edward F. Moore's 1959 self-reproducers

[dpbsmith]

How is this any more impressive than what Edward F. Moore did in 1959? There was a Scientific American article about it, and I saw him demonstrate it at a lecture in the late sixties.

Basically he had a two-dimension row of pieces, rather like jigsaw puzzle pieces, held upright between two pieces of plexiglass. The pieces had just the right shape; they were basically diamonds with a truncated bottom (so they sat in one particular orientation) and sides. Initially they'd all be sitting flat. He would "add heat" by shaking the contraption laterally. Nothing would happen, because the blunt ends would hit against each other.

Then he'd take two of them and tilt them and slide them together, producing a single two-celled "organism." There were little hook-like projections that held them together.

He would shake the thing again. This time, because the two "cells" were tilted, their ends would scoop up underneath the blunt ends of the neighboring "cells," tilting them up into the proper position to hook together too.

So, when he shook the thing in its initial state, nothing would happen. But when locked two of them together into a "creature" and shook them, they caused the other "cells" to assemble into two-celled organisms just like the original one.

In other words, the organism had created copies of itself.

It really worked; there was no deception; after the lecture practically everyone swarmed around and played with the thing and it didn't require any sleight-of-hand twists of the wrist.

I thought it was a strained tour-de-force then, and I think these "self-replicating robots" are just a fancier example of the same thing.

Dyson

[Rand310]

Freeman Dyson had the great example of self-replicating robots in his book 'Disturbing the Universe.'

Imagine sending a quarter-pound payload of a well-programed robot of such construction to something like one of Jupiter's icy moons. It is as small as needed to do the following tasks: replicating twice, grab a small piece of the ice on the moon as cargo, and then launching itself with some element in the ice as fuel towards mars. That's all it is programmed to do.

In x amount of time you have a mars with oceans. Astroid mining could also work on similar principles.

Regardless of how plausible or crazy the above ideas are, the concept is gorgeous for people... The investment in one such machine can yield payoffs of millions/billions of man-hours of labor, in places man can exist etc.

There is always the observation of slavery/exploitation if such a machine can replicate. Or even fears of Matrix/virus-like behavior which continues uncontrollably. But it is an interesting idea to think about. Rarely can a human investment of time provide such a staggering turnaround in product.

Interesting concept, even if it does still resemble science-fiction.

Re:More!

[gaanagaa]

1:00 X-Robot
2:00 Y-Robots X/2#1 and X/2#2 + X
3:00 Z-Robots X/4#1 and X/4#2 +X+Y
4:00 W-Robots X/8#1 and X/8#2 +X+Y+Z
Bipp...Bipp...Bipp...Bipp......Beeeeeeeeeeep

Re:More!

[Rei]

The thing is, self replication isn't a completely clearcut situation. Everything has inputs, so the issue is how distant from your inputs you can get. In an extreme example, I could say that a rock with a broken stick attached to it is a self replicator, because if you put the stick of a pair of rocks connected by a stick under it, the rock will break the connecting stick and have created two more copies of itself.

For a more real-world example, look at malformed prions involved in BSE (mad cow disease). In a way, they self replicate - a single malformed prion can end up leaving your brain full of them. On the other hand, their input is simply a normal prion - they just fold it into their misformed shape. Is that really replication? Yes, but it's a pretty simple form of replication with very limited inputs.

A real feat would be robots that could self replicate with their only material inputs being, say, raw minerals and energy. That would be closer to what bacteria do.

Re:Torrent please?

[charon_1]

that way the movie can self-replicate just like the robots!
har har har.. thanks folks i'll be here all night.

Re:Not exactly "gray goo"

[Anonymous Coward]

Bah, and where do these humans get off saying they replicate. Stars just hand them all the carbon they need on a silver platter. If they could do it from pure hydrogen, that'd be replication.

Re:Not replication

[Mr Bubble]

I think the allure here is that the building blocks can eventually be extremely small, and, since they are uniform, easily shipped to, say, Mars.

Since every part must be constructed from the same basic building block, construction algorithms will be the same (or similar) regardless of the component. I would imagine this rules out surprises and the need for specialized spare parts.

Furthermore, inventory considerations and calculations are greatly reduced as the relative importance and fragility of various parts does not need to be assessed.

So, while it's not replicating itself from raw materials, I think this is a logical first step.

Re:More!

[poopdeville]

Life is not defined by "having a metabolism." One could define life that way, but it would capture lots of things we wouldn't consider alive. Fire, for instance, has a metabolism. Even these robots, whom you say are not alive, have a metabolism. Moreover, this definition misses entities that debatably are alive, such as biological viruses.

It is interesting to note that every definition proposed so far misses things that are "intuitively alive" and includes things that intuitively aren't. There are plenty of great books on the Philosophy of Life out there -- I suggest you read some.

Re:More!

[ardor]

You know, some firefighters swear that fire is alive sometimes. It reacts to you, eats, replicates ... of course, a small campfire does not look like this, but a whole building in flames is a different story.

About the definition of life, a while ago I heard the possibility about everything be alive. Since a rock reacts upon heat, water, etc. it is not "dead". As for replication, there are animals that do not replicate or try to self-sustain themselves. OK, these are mostly guards protecting a queen, but lifeforms do not have to replicate itself directly. However, there are similar patterns on all scales. A human is born, grows, his personality thrives, later he gets old and dies. Same applies to all animals and plants, all civilizations, all celestial bodies, galaxies, even to the universe (if its finite, that is).

IIRC, the conclusion was that energy=information=life. Highly hypothetical stuff, though very interesting.

Re: reproduction vs self-assembly

[johnrpenner]

this is not reproduction, this is self-assembly.

to change the definition of reproduction to also mean
self-assembly is simply to decieve ourselves.

unlike animals -- which do two discrete things:

1. NUTRITION: break down the substance of their 'food'
at a molecular level and transforming it into the
content of their own bodies (in this instance, the
electrical power for the servo motors and processing
should come from what is being consumed).

2. REPRODUCTION: creating the necessary structures
such that a similar being can occupy a seed-structure
which also takes up nutrition from the environement in
a manner that is consistent with the parent organism.

these robots have demonstrated neither DIGESTION,
nor REPRODUCTION, but merely self-assembly.

this is different than a PLANT -- which given
only MUD, LIGHT, and WATER can transform that
mud into FLOWERS -- that is digestion. after
it has done that, the reproductive phase of
the plant has already quite different qualities.

plants are able to seperate out the
individual mineral qualities it encounters in
the soil, and include them in their structures.

but for these robots -- they are not using raw materials
like WATER, MUD, and LIGHT -- if it were, you could
stick it into a puddle of mud, add water and light,
and watch it do its thing -- creating gears and
generating power for servo motors out of mud, water
and light.

the cubes supplied here are already PRE-MANUFACTURED
(conveniently added into frame for the video). so if
you wanted to be truthful about the matter -- you would
have to include all the processes that humans performed
to get the pre-manufactured cubes into place for the
self-assembly operation.

but in the case of reproduction, there are at least two
stages present which are absent here: it must first draw
NUTRITION for its activity from the environment and transform
that into the raw materials for sustaining its activity.

then, after it can EAT, it goes on to a second activity
of reproduction (creating another like itself, which can
also take the raw substance through digestion, and
sustain itself).

changing the definition of reproduction
to include what is actually self-assembly
does a diservice to clear understanding of
the phenomenon.

j.