Alt-BEAM Archive
Message #08435
To: beam@sgiblab.sgi.com
From: "Timothy Flytcher" flytch@hotmail.com
Date: Sat, 18 Dec 1999 22:51:35 PST
Subject: [alt-beam] Re: Carbon fiber
This is true but then so will a lot of splinters... Their not as bad as
redwood! But equally on par with fiberglass... I have worked with the stuff
and find very little bad :) The way I cut rods is to use a #11 exacto and
roll it on a hard flat surface(I use class)... use lots of pressure... but
not enough so as to cause the ends to shatter... practice on one end... you
should be able to cut a 3mm pice off and have it come off intact... This is
when you know your doing it right :)
Timothy...
>just one thing on safety, i fly R/C helicopters (they run on methenol and
>nitro) and alot of people use carbon fiber blades, but when i have been
>told that the splinters are very dangerous and once the get under your skin
>they'll never come out. It's cool stuff though.
>
>David Perry
>
> -----Original Message-----
> From: adam-m
> To: beam@sgiblab.sgi.com
> Date: Sunday, 19 December 1999 9:36
> Subject: Carbon fiber
>
>
> Bot frame tip:
>
> I picked up some carbon fiber rods from a local kite store. They had
>all different sizes, i got their thinnest (about 1mm) and one about 2.5mm.
>
> Wow! Extremely strong, very light, and neat flexible properties on
>the thin stuff (great rear suspension on a trailing wheel). It makes for
>very strong light frames.
>
> You can superglue it, or get that copper sticky tape from stained
>glass supply places (which is dynamite for other things too..). A little
>wrap of the copper tape on the ends and you can solder joints together.
>
> The Carbon fiber is slightly conductive - which i found out annoyingly
>after wrapping some transistor pins around it wondering why nothing worked
>- so keep electricals non contact.
>
> The rods were very inexpensive. I spent $6 CAD on the 2 1mm and 1
>2.5mm.
>
> Try it, great stuff.
>
> /A
______________________________________________________
8436 Sat, 18 Dec 1999 23:15:56 PST [alt-beam] NiCads... beam@sgiblab.sgi.com "Timothy Flytcher" >I brought this up a few
>days ago, but interest seems light.
I for one am very interested... I am building my house right now so I have
little time for experimentation... But I am! building in a beam park in the
living room window... I don't want to put any lights there and plan on being
there in the evenings... so I would love to build bots that bask in the
afternoon sun then provide some extended entertainment in the evening... The
window is on the south east corner of the house so it will get direct
afternoon till dusk sun :) I guess I just limited my bots as
entertainment... But that is how I feel about them right now...
Timothy...
> > Now your robots get big and ugly.
>Not really the same thing, at least to me.
> > If you want to make big bots that only run outside in direct sunlight,
>then
> > go for the blue PV's.. They will kick ass, and really go fast. BUT
>take
> > them inside and prepare to be underwhelmed.
>But, lets put a second solar array onto that big ole' ugly bot. Let's hook
>that to a NiCad pack and devise a circuit to switch to the batteries when
>the
>light levels are less than optimal. You now have a bot that kicks ass in
>the
>sun, in the shade, in the house, and in the dark. I brought this up a few
>days ago, but interest seems light. I plan to pursue this line of thinking
>and will refer to the battery circuit as robotic fat. A bot without fat
>will,
>and do, die in lower light levels. They are complete corpses in the dark.
>If
>your bot is roaming around all day in bright sunlight, why not build up a
>secondary reserve to keep it going in more adverse conditions? Yes, it will
>be somewhat larger, but it's performance would be much improved. Of course,
>it would not fit ANY of the guidelines of the BEAM games, but it would out
>perform any bot entered. And, you could see interaction, even in little to
>no
>light, without the need for stop motion camera work. A bot that works in
>real
>time, all the time. Sounds good to me.
>
>
>See ya,
>Jim
>http://www.geocities.com/SoHo/Exhibit/8281/beamart.html
>ICQ# 55657870
______________________________________________________
8437 Sun, 19 Dec 1999 03:27:33 EST [alt-beam] Re: NiCads... beam@sgiblab.sgi.com JVernonM@aol.com In a message dated 12/19/99 2:23:47 AM Eastern Standard Time,
flytch@hotmail.com writes:
> I for one am very interested... I am building my house right now so I have
> little time for experimentation... But I am! building in a beam park in
the
> living room window...
Good for you! I wish I could do that myself. I have a plan for a BEAM park
that will be great if I ever get to it. I do need to do something though,
I've built so many bots that I have no where to keep them. I don't want to
stick them on a shelf to gather dust, after all, the whole idea is to enjoy
them. As to the power issue, if I get anywhere I'll post my findings. A
combination of the D1 and a good day time solar engine sounds like the
ticket. I've tried the D1 with up to a 10F cap and the performance is very
disapointing. On my Jasmine plant I only get about half an hour of blinking 8
micro LEDs. I would imagine a Unicore (which I think is the best candidate
for this) with two gearmotors, would drain that 10F cap in just a few
minutes, no good (besides, it's as big as one of those personal juice cans,
and gets a full charge from the large solar cell in under an hour of full
sun). The logical solution is a battery pack instead of the cap. The only
problem that I anticipate is setting the "on" level of the D1. The range of
coming on to soon versus not coming on fully is very small. Also, I'm not
sure about using the solar cell as the light sensor (as the D1 does), seems
that a good ole CDS cell would be more sensitive and tweekable. I envision
bots that work constantly. Day or night, no matter the light level. Assuming,
of course, that the critter gets some sun during the day. I thought of this
while watching my Jack Russell Terrier playing in the yard. He has an almost
inexhaustible supply of energy. A vast reserve used to play, explore, and get
into trouble. Then, I thought, the robots we build have no such reserve. They
eat and move, eat some more and move some more. No food, no motion. We
emulate biologicals, but have never considered a power reserve for sustained
operation or frivolous use. Our bots are anorexic! They need some fat to get
them through the night. Imagine how much more useful a window cleaner or a
sweeper bot would be if it never stopped. We have come to refer to the non
operational time as sleep time. But, sleep time is usually associated with
recharging ones energy reserves. The sleep time that we often refer to
(outside of the time it takes for a super cap to fire, and really, that
should be called eat time) is really dead time. They are dead as a door nail.
A bot with a power reserve would also keep a microprocessor "rider" going as
well, allowing for more complex behavior. It seems like the natural next step
to me. Sorry for the book, I'm just excited that someone mentioned the idea!
See ya,
Jim
http://www.geocities.com/SoHo/Exhibit/8281/beamart.html
ICQ# 55657870
8438 Sun, 19 Dec 1999 10:54:37 -0500 [alt-beam] Just a thought beam@corp.sgi.com Ian Tinker Just a thought on solar powered BEAM Bots
Solar powered floor sweeper or window washer ??? seems like a very
inefficient way to collect and use solar power, as most of your house is in
the dark. Why not put the collecters where they will see the sun all of
the time, on the roof charging a 12v car battery "Feeding Station". The
available solar collectors for the roofs of houses are larger more
efficient and the battery bank storage method could run a whole flock of
BEAM bots all nite, with provisions for those cloudy days. The robots
could have recharging points through-out the house. Battery power seems
like the way to go for "nite crawlers".
Just my 2 cents
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