Alt-BEAM Archive

Message #03805



To: beam@corp.sgi.com
From: Chiu-Yuan Fang chiumanfu@home.com
Date: Thu, 27 May 1999 15:35:06 -0700
Subject: [alt-beam] Re: PBS special- Poppers


Here's two comments on the BEAMant 6.X from Zoz.
Msg 10 and 11 at the Yahoo BEAM robotics club.

If you look carefully on the bottom view of the hextile "photovore" you'll see
inscribed: "BA 6.6" and something that looks either like 3/16/1998 or 5/16/1998.
In either case, Tilden calls the robot a BeamAnt although it is substantially
more complex than the older ones.

Calling it a photovore is rather deceptive since it can exhibit many more
behaviors than one of those. It consists of a bicore that is controlled by two
IR sensors, much like a bicore head which is embedded in another bicore that you
could consider its "central oscillator". The two outputs of the outer bicore are
routed through Nv neurons and connect to one pole each of two motors.

A pair of touch sensors go through Nu (integrating) neurons and those outputs
connect to the other poles of the two motors. In effect, you get what Mark calls
an XOR motor driver -- the motor only turns if the output of the Nv neuron is
DIFFERENT than the output of the Nu neuron. Also, since the difference can be
either way (high-low vs low-high) the motor can turn in either direction.
Finally, the connections to the motor can be so that the Nu and Nv are on the
same or opposite sides (cross-over) of a given motor.

All of the resistors in the top picture of this robot are used for setting
parameters, "programming" if you will. I've seen a small colony of the robots
collect (ok, it really was pushing rather than collecting ) similar
brightness objects (dark and light) onto differently colored sections of a
mini-RJP.



The very handsome "hextile photovore" is actually Tilden's addition last year to
the BeamAnt series. It is substantially more complex than the older ones, having
a embedded suspended bicore and a pair of Nv drivers connected to one side of
two motors and a pair of Nu neurons connected to touch sensors connected to the
other side of those motors. As a result, a given motor is "XOR driven" by one Nv
and one Nu neuron. The resistors in the top view set parameters, "programming"
the robot if you will. A colony of these robots, half with one set of parameters
and the other programmed differently, can sort objects of two different
brightnesses.

You can see "BA 6.6" inscribed on the bottom view (which, oddly, doesn't have
motors) and a date: either 3/16/1998 or 5/16/1998 (probably the former.)

JVernonM@aol.com wrote:
>
> I sent this message last night (this morning?) but like a couple others it
> didn't go through. I'm sending it again, so I apologize if anyone gets this
> twice.
>
> I do have a couple of positive comments about the PBS special (NO, NO :)).
> Two things that really caught my eye were a little popper looking bot that
> twitched VERY rapidly and bug like. It must have had a very small cap. It's
> movement was very interesting to watch. Also, and what really got my mojo
> going, was a little BEAMANT 6 (I guess) that was made of two hextiles stacked
> on top of each other like a CPU bot. It's movement was truly amazing from my
> experience with these critters! I mean it moved constantly with a very fluid
> motion. I gotta know what's under the hood there. Is it a Bicore jobbie with
> a PM1 circuit to get that rapid, constant movement? Does it therefore have a
> sleep phase? If anybody has any straight poop on this thing I'd love to hear
> it. I ran the tape over and over on that little bug, and was amazed at it's
> activity. Dave, how's that for a kit? What would that be 3 or 4 stacked in a
> row for R&D :)? I'll wait (I want one).
> Jim

--
Chiu-Yuan Fang
chiumanfu@home.com
ICQ=5614919
http://www.geocities.com/SouthBeach/6897/beam2.html

------------------------------------------------------------------------

eGroups.com home: http://www.egroups.com/group/alt-beam
http://www.egroups.com - Simplifying group communications



Home