Alt-BEAM Archive

Message #11400



To: beam@sgiblab.sgi.com
From: BUDSCOTT@aol.com [mailto:BUDSCOTT@aol.com]
Date: Mon, 6 Mar 2000 13:31:10 -0800
Subject: Re: gumby legs



note on gumby legs, i've tried some 8-gauge wire on my bot which wasn't
hardly stiff enough for good legs (it is a bit large, but still) walkers
tend
to work better with nice sturdy legs that won't flop around too much. If all

else fails, go to a department store and buy some wire hangers, those things

are so stiff, its difficult to cut them with side cutters, and even harder
to
bend them! again, it all is reletive to the bots weight.

-Spencer



11401 Mon, 6 Mar 2000 22:46:20 +0100 [alt-beam] Re: Forgive me for being such an arrogant fool, but... "Thomas Pilgaard" > Ugh and double ugh!
>
> Look folks, we don't really have to argue about the definition of
> "emergent
> behavior". The term has been pretty well defined by the a-life and
> complexity theory people and, although the concept may be somewhat
> difficult to grasp or believe, at least it has been described clearly.

I don't see why we shouldn't discuss it just for the discussion of it. For
instance ...

> >The idea that complex systems, such as life, are actually the emergent
> >behaviors of systems with many elements that operate according
> to simple,
> >local rules (Artificial Life).

... in this description it is assumed that the term life !is! a system. A
system - as near as i can translate it - is defined in my lexicon as:

"a structured whole, whose parts are interconnected according to specific
rules, laws or principles."

And emergence can - as near as I can translate it - be defined as:

"... that as whole properties appear, that cannot be explained via the
properties of the individual parts; the appearance of phenomena that
describes a higher level which cannot be explained by a lower level, where
they have their origin."

Now, in my opinion there's a difference between an object truly having
properties of life (assuming that these can be extracted and mimicked) and
us ascribing properties to an object, like you do below. Surely, we wouldn't
alone be interested in making something just seem convincing to on-lookers
(although the effect is quite stunishing: when my nepheu aged 1 1/2 yrs. saw
my photopopper he immediately said "Itsy bitsy spider!" which really had me
thinking). Furthermore one can distinguish between something having
properties of life and actually !being! alive.

Then there's the question of life being a system. For one, there's a problem
in defining life (see "Defining life. Explaining emergence", Claus Emmeche;
can be found on http://www.google.com). Then, if the term life is taken an
unquestioned premise there's still a problem in saying that life is a system
since a system implies formalising and expliciting the structure that
determines the system as a whole. In this process of formalisation lots of
stuff is left out - the term of life described as a system is 'cut to the
bone' so to say. This is IMHO what we see in BEAM. A few - though very
representative in some respects it seems - variables defines the concept of
a creature.

... I'm not sure where this is going actually. You may see it as my two
cents. Sorry if it is a bit off topic.

Thanks,

Thomas


>
> In other words, looking at systems from the bitty little pieces, from the
> bottom up; seeing what happens when a bunch of stuff gets to
> interact -- do
> patterns appear? More importantly (at least with regard to BEAM
> robotics)
> is: do USEFUL patterns appear? Does it appear to be lifelike? For
> example: there is nothing whatsoever in the construction of Mark's
> "snakebot" that would suggest anything more that some tubes, motors and
> electronics. However, the sensation when you hold it (powered up, of
> course) is so lifelike that it is eery.
>
> In any case, I strongly disagree with Bruce's definition.
>
> chipuser's sound questions sounds a lot like Tilden's
>
> >"In other words, robogenetics through robobiologics."
>
> taken straight off of the LANL page (that is,
> http://nis-www.lanl.gov/robot/). Of course, on the same page Mark says
>
> >"The problem is that such a concept requires self-reproducing
> robots which
> >won't be possible to build (if at all) for years to come. A solution,
> >however, is to view a human being as a robot's way of making another
> >robot, to have an annual venue where experimenters can let their
> creations
> >interact in real situations, and then watch as machine evolution occurs."
>
> however, it isn't emergence that is occurring but evolution (or what most
> people would call technological development).
>
>
> jab
>
>
> ------------------------------------------------------------------
> ----------
> ------------------
> At 09:08 PM 3/5/00 -0800, Bruce wrote:
> >chipuser wrote:
> > >
> > > Is it safe to say emergent behaviour = emergent understanding
> > > on the builder's part or the learning of the builder instead
> > > of the bot ?
> >
> >I wouldn't say they are synonymous, but they sure are closely linked.
> >The behaviour is there, whether you recognise it or not. But it isn't
> >much use if you don't recognise it. Recognising the emergent behaviour
> >is definitely "learning of the builder".
> >
> >Emergent behaviour is not precisely robot learning. Connect some
> >mechanical parts to an electronic circuit, and produce some repeatable,
> >robust behaviours under a variety of conditions -- that's emergent
> >behaviour (in my view -- subject to much debate, no doubt).
>
>

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