Alt-BEAM Archive
Message #12908
To: beam@sgiblab.sgi.com
From: SkavenArmy@cs.com
Date: Sat, 1 Apr 2000 12:06:04 EST
Subject: [alt-beam] Re: Biped
ITS OOMPH OR HUMPH!
12909 Sat, 1 Apr 2000 14:09:13 EST [alt-beam] Re: Ideas................. was --- Biped beam@sgiblab.sgi.com BUDSCOTT@aol.com Somebody was talking about lowering the center of gravity, that would be the
best shot to make a stable walker. Have any of you ever played the
Playstation game "Metal Gear: Solid", now if you look at the mech in that
you'll see that the legs to extend all the way out, they kinda crouch. If you
have time next time you go to a book store, go to the video game strategy
guides and look for Metal Gear solid. You'll see what i mean! I have a
feeling that we'd need to start there and then go up from that. What i was
thinking was to put the motors in the feet, and use a belt drive system to
turn the knees, that might clear out the bulkyness. The best way to figure
out a decent gate is to walk in a straight line, completely normally and pay
attention to the occilations you make, When you walk there are going to be 7
different occilations, 2 x arms, waits, hips, 2 x knees. Then all you need is
an incredibly complex microcore system.
-Spencer
<http://www.botic.com/users/beamstop>
not a robot scientist
not a college major
not a grad student
not a professor
not a very organized person
just Spencer (isn't that impressive enough?)
12910 Sat, 1 Apr 2000 14:48:11 EST [alt-beam] Reverser beam@sgiblab.sgi.com BUDSCOTT@aol.com Okay, one quick question, how do you hook up a 240 Reverser to the motors! i
got the circuit and i have a good understanding of how it works, but how does
one hook up this circuit! Thanks a ton!!!!
-Spencer
<http://www.botic.com/users/beamstop>
not a robot scientist
not a college major
not a grad student
not a professor
not a very organized person
just Spencer (isn't that impressive enough?)
12911 Sat, 01 Apr 2000 11:33:24 PST [alt-beam] Re: Ideas................. was --- Biped beam@sgiblab.sgi.com "sebastiaan van Vliet"
Maybe this moight help you: Go to a cheap shop and buy yourself a nice
kitchen timer (butt... I am not making a gearbox at a...) Let me finish!
In there is a great and nice little wheel that goes left, righ,left,right.
release it. Try to get the brass thingies that keep it in place too. Ig you
haven't seen them before, they are suspended like this
Upper part of OTU
/\
/\
II
II Wheel axis
II
II
\/
\/
lower part
It is a very low resistance suspention.
now cut a piece of paper the size of the wheel and devide it in two equal
parts. cut away 1 part. now glue one piece of paper on the weel,put a tiny
weight on the opposite side of the paper and put the whole thing in your
robot. (vertically) Now make two LED/Photodiode combinations and place then
respectively under and above the wheel, so they make an angle of 90 degrees.
Voila.
Of it leans to a side, the weight will turn the wheel to that side, making a
photodiode see the led and trigger a motor that sraigtens the bot up.
("seeing the led is motor turnihg -say- right, not seeing is turning it
left, so the bot is always active in levelling itself!
- four diodes/LEDs can be done too, with onlu a third of the wheel open. The
bot has a position in wich it is straight and id not levelling, but as the
bot is meant to walk, it probably won't use it, so two is simpeler
______________________________________________________
12912 Sat, 1 Apr 2000 16:42:17 EST [alt-beam] Photovore competitions beam@sgiblab.sgi.com BUDSCOTT@aol.com Hey everybody! I was wondering if anybody has tried building and trying the
new photovore arena? I think i might build one eventually (before the WCRG)
but i was wondering if anybody had some insight as to decent times to beat on
that? This is kindof off the solarroller e-mail. Also...PM1, i finally found
it on beam-online, to think i've overlooked all this time! Does anybody have
anygood tips for construction? Thx!!!
-Spencer
<http://www.botic.com/users/beamstop>
not a robot scientist
not a college major
not a grad student
not a professor
not a very organized person
just Spencer (isn't that impressive enough?)
12913 Sat, 1 Apr 2000 16:36:40 EST [alt-beam] Re: replies beam@sgiblab.sgi.com BUDSCOTT@aol.com no, its always like that, its probably that way to keep people from excluding
others from their conversations (except ones that don't apply!). At least
thats what i think.
-Spencer
<http://www.botic.com/users/beamstop>
not a robot scientist
not a college major
not a grad student
not a professor
not a very organized person
just Spencer (isn't that impressive enough?)
12914 Sat, 1 Apr 2000 16:34:48 EST [alt-beam] Re: Ideas................. was --- Biped beam@sgiblab.sgi.com BUDSCOTT@aol.com In a message dated 4/1/00 11:14:34 AM Central Standard Time,
SkavenArmy@cs.com writes:
<< found an elastomer that u put itnside a peice of heat skrink , put in
some
conductive fluid, attac electrodes to the inside , seal the nes and your
ready to go... >>
Where did you find that at, that would be cool to try out!
-Spencer
<http://www.botic.com/users/beamstop>
not a robot scientist
not a college major
not a grad student
not a professor
not a very organized person
just Spencer (isn't that impressive enough?)
12915 Sat, 1 Apr 2000 13:51:09 -0800 [alt-beam] Re: Ideas................. was --- Biped "'beam@sgiblab.sgi.com'" Wilf Rigter Steve, your observation is correct but for reasons that you may find
surprising.
In a 240 bicore, the more precisely you match component values, the more
erratic the pulse width. Huh? The reason is as follows: An ideal bicore with
matched components and 240 input thresholds near the (symmetrical) center of
the power supply has a longer time constant (lower frequency) than a bicore
with mismatched components or an asymmetric threshold voltage (HCT240). This
also increases it's sensitivity as switching occurs much later as the
exponential input waveforms decays exponentially towards a narrow threshold
region near the center of the supply. When the slope of the decaying input
voltage is almost parallel to the threshold voltage, the bicore transitions
will be triggered by noise and the output frequency will jitter. This also
sheds some light on ways in which the bicore is influenced by motor loading
feedback. If you have a scope and like to observe the input waveforms, you
may have to reduce the bicore resistor value to 100K because, with a 3.3M
bicore resistor, the scope probe input resistance will disturb the delicate
balance and affect the oscillator duty cycle or even kill oscillation.
enjoy
wilf
> -----Original Message-----
> From: Meabadboy@aol.com [SMTP:Meabadboy@aol.com]
> Sent: Friday, March 31, 2000 11:39 PM
> To: beam@sgiblab.sgi.com
> Subject: Re: Ideas................. was --- Re: Biped
>
> In a message dated 4/1/2000 12:45:11 AM Eastern Standard Time,
> SkavenArmy@cs.com writes:
>
> << a good timing unit isthe "atomic clock ic kit" from mondo-tronics.i >>
>
>
> I am basically useing the BEAM circuits ~ or more to the point ~ the
> modification of them ~ as the basic clock for the robot ~ one problem with
>
> what I have seen in my applications was that the BEAM circuits do odd
> things
> sometimes ~ I have a textronix o-scope and when testing the motor/gate the
>
> clock would see for lack of better words ~ "a hickup..........??" ~ it may
> be
> some diference in the manufaucturing tolerances of the caps ??? ~ i used
> all
> 1% resistors ~ or it could be in the gate of the 240 it's self ~ not too
> sure
> ~ I have changed out the 240 chip with a new one at least 5 times and have
>
> used different caps.
>
> most of the time it works (ie clocks) correct
>
> could be all the soder fumes ~ or the coffee ~ lol
>
> From all I have read on this list from other people ~ it must be an
> inherent
> trate of BEAM circuits to have this ODD trend in charge of the caps and
> fire
> time on the gate differences ~ maybe even by design???
>
> or dare i say a personality trate??? ~ some genitic flaw in a neuron ~ lol
>
> but anyway ~ $90 is a wee bit out of the budget for this gye im building ~
> my
> wife thinks it's silly enough ~ lol
>
> steve
>
>
>
> ~ I thought about what you mentioned above ~ one of the students in a lab
>
> used a sim clock to what you mentioned ~
12916 Fri, 01 Jan 1999 13:38:51 -0700 [alt-beam] Re: Photovore competitions beam@sgiblab.sgi.com Dave Hrynkiw At 02:42 PM 4/1/00 , BUDSCOTT@aol.com wrote:
>Hey everybody! I was wondering if anybody has tried building and trying the
>new photovore arena? I think i might build one eventually (before the WCRG)
>but i was wondering if anybody had some insight as to decent times to beat on
>that?
Well, I've got 2 built, and material for 4 more on hand. We based the
overall time for the event by using a pair of PhotoPoppers as "benchmark"
devices. If you can get your device to the middle in under 3 minutes (about
the time for a PP42), you're doing great!
-Dave
---------------------------------------------------------------
"Um, no - that's H,R,Y,N,K,I,W. No, not K,I,U,U, K,I,_W_. Yes,
that's right. Yes, I know it looks like "HOCKYRINK." Yup, only
2 vowels. Pronounciation? _SMITH_".
http://www.solarbotics.com
12917 Sat, 1 Apr 2000 17:33:02 -0500 replies Joe
Hi,
I've noticed that this list (as separate from my other list membership), has
a strange reply function.
Normally, I can go to Reply, and send a private e-mail to the sender...OR go
to reply all, and respond to the list members.... With BEAM...it all goes to
the entire list, regardless of how I address it! Is that normal? Or is Bill
getting back at me for some obscure offense that I'm not aware of???
Joe
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