I want to get some components from USA through a friend when he returns to
India.Can I get a list of retailers(resellers) of semiconductor components
in Washington DC area.If not readily available where to look for it.Thanks a
lot.
Gopi Menon


[Non-text portions of this message have been removed]

They are pretty simple. Polarity shows direction,
amplitude shows displacement. Essentially frictionless
operation and virtual immunity to contamination make
them very attractive.

http://www.rdpelectrosense.com/displacement/lvdt/lvdt-principles.htm

http://geoinfo.usc.edu/nees/Excel_data/Specifications/018-021.pdf

http://www.isa.org/journals/mc/feature/1,1162,320,00.html

http://www.ni.com/sensors/lvdt.htm

http://www.efunda.com/DesignStandards/sensors/lvdt/lvdt_intro.cfm

I've added these and other links to the SumoRobot
Yahoo group. Look under "Schematics, Plans, Etc."

http://groups.yahoo.com/group/sumorobot/links/

However, LVDT's response time is limited to about
1/10th the period of the AC signal used. If you really
need this to move quickly and those are 4 fixed
positions that won't change once set,
opto-interruptors may be the simplest way to go.

Steve

--- Bob Dyer <bd@...> wrote:
> Steve,
>
> I don't know how I'd actually make a linear pot, but
> I've seen
> string/pulleys on rotary pots. If I have to create
> this "function" without
> the pot, I'll probably make a linear encoder. But
> making anything is more
> than I want to mess with on this project.
>
> I've got a translation stage that I need to move
> about 7 inches and do it
> fairly quickly. I need to verify its position at 4
> different points along
> its travel. I was going to use 4 different
> electro-optic sensors along the
> path, but I think overall that'll be more
> complicated to wire and setup.
> This should be much easier to do, plus I can get
> position anywhere along the
> path, not just at a few discrete points.
>
> Bob


__________________________________________________
Do You Yahoo!?
Great stuff seeking new owners in Yahoo! Auctions!
http://auctions.yahoo.com

US digital makes linear encoder strips.  It's $19/ft and comes in several
resolutions.  I've been using the 1440 count/in in a bunch of projects.

      -Kenneth
       (Unit 3's in trouble and it's scared out of its wits) -Geddy Lee
----- Original Message -----
From: "Steve Greenfield" <polymorph@...>
To: "SeattleRobotics Mailing List" <seattlerobotics@yahoogroups.com>
Sent: Sunday, February 03, 2002 9:55 PM
Subject: RE: [SeattleRobotics] Linear Displacement Transducer


> They are pretty simple. Polarity shows direction,
> amplitude shows displacement. Essentially frictionless
> operation and virtual immunity to contamination make
> them very attractive.
>
> http://www.rdpelectrosense.com/displacement/lvdt/lvdt-principles.htm
>
> http://geoinfo.usc.edu/nees/Excel_data/Specifications/018-021.pdf
>
> http://www.isa.org/journals/mc/feature/1,1162,320,00.html
>
> http://www.ni.com/sensors/lvdt.htm
>
> http://www.efunda.com/DesignStandards/sensors/lvdt/lvdt_intro.cfm
>
> I've added these and other links to the SumoRobot
> Yahoo group. Look under "Schematics, Plans, Etc."
>
> http://groups.yahoo.com/group/sumorobot/links/
>
> However, LVDT's response time is limited to about
> 1/10th the period of the AC signal used. If you really
> need this to move quickly and those are 4 fixed
> positions that won't change once set,
> opto-interruptors may be the simplest way to go.
>
> Steve
>
> --- Bob Dyer <bd@...> wrote:
> > Steve,
> >
> > I don't know how I'd actually make a linear pot, but
> > I've seen
> > string/pulleys on rotary pots. If I have to create
> > this "function" without
> > the pot, I'll probably make a linear encoder. But
> > making anything is more
> > than I want to mess with on this project.
> >
> > I've got a translation stage that I need to move
> > about 7 inches and do it
> > fairly quickly. I need to verify its position at 4
> > different points along
> > its travel. I was going to use 4 different
> > electro-optic sensors along the
> > path, but I think overall that'll be more
> > complicated to wire and setup.
> > This should be much easier to do, plus I can get
> > position anywhere along the
> > path, not just at a few discrete points.
> >
> > Bob
>
>
> __________________________________________________
> Do You Yahoo!?
> Great stuff seeking new owners in Yahoo! Auctions!
> http://auctions.yahoo.com
>
> To unsubscribe from this group, send an email to:
> SeattleRobotics-unsubscribe@egroups.com
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>

We would like to remind you of this upcoming event.

Monday Night Chat

Date: Monday, February 4, 2002
Time: 7:00PM - 9:00PM PST (GMT-08:00)

Monday Night Chat happens every Monday at the SRS. Come ask
questions or offer advice live.

Directions:

The chat requires that you use an Internet Relay Chat (IRC)
program. Details on finding one are below.

For you experts, the chat is held on us.chatjunkies.org in the
#SeattleRobotics group.

For Windows users:

See the SRS website at

http://www.seattlerobotics.org/contact.html#Monday

We would like to remind you of this upcoming event.

Monday Night Chat

Date: Monday, February 4, 2002
Time: 7:00PM - 9:00PM PST (GMT-08:00)

Monday Night Chat happens every Monday at the SRS. Come ask
questions or offer advice live.

Directions:

The chat requires that you use an Internet Relay Chat (IRC)
program. Details on finding one are below.

For you experts, the chat is held on us.chatjunkies.org in the
#SeattleRobotics group.

For Windows users:

See the SRS website at

http://www.seattlerobotics.org/contact.html#Monday

My experience with the IR sensors is that most people use them incorrectly,
including me.

If you read the datasheets for the IR receivers, the signals must be two
different signals.  The first signal is 40 kHz (depends on when IR Receiver
you use), the second signal is a square wave at 1667 to 2500 Hz.  When the
second signal is high, the IR must be modulated at 40 kHz.  Most people
forget about the second frequency.  This improves the reliability.

Second, use a sensor that has a plastic shield the blocks visible light.
The Panasonic ones that Digikey sells does this.  I have circuits that work
under direct sunlight.

The main problem about IR reflective sensors is that they are specular
sensors.  When the IR hits an object, it doesn't neccessarily bounce
straight back to the receiver.  It bounces some other direction.  Pure
physics tells you that this will happen.

One way to get around this problem is to use very high intensity IR LEDs.
This works a whole lot better, but there is a drawback, it starts picking up
reflections from objects on the other side of the room.  So there has to be
some trade off when selecting the intensity of the IR LEDs.

I have heard rumors that the Japanese use a IR sensor that is extremely
accurate for sumo applications.  I have also heard that these sensors cost
$120 each.  I have no idea what they are, but I would love to get my hands
on one.

I think Ultrasonic sensors would work better than the IR reflecticve
sensors, but I personally have not used them.

I think the best sensors would be Kens Laser Ranging systems.  It probably
will be too complicated for a mini sumo, but it should work for a 3 kg sumo,
or any other type of robot.

Pete
petem@...

----- Original Message -----
From: "Doug Kelley" <doug.kelley@...>
To: <SeattleRobotics@yahoogroups.com>
Sent: Sunday, February 03, 2002 10:07 AM
Subject: Re: [SeattleRobotics] Thoughts on an encoder article.


> It seems IR is a little unreliable for sumos.  Is anyone doing anything
with
> sonar?  It's slow, but might work well for minis.  The little one that
Acroname
> sells seems like it would be ideal.  It's low current and (I think) has a
range
> of about one meter.
>
> I'm not suggesting sonar as the sole sensor but it might complement IR
nicely
> since it's immune to light and detects objects over a relatively wide
beam.
>
> Doug
>
> lbarello@... writes:
> >You could implement synchronous detection.  I.e. gate the illuminator
> >and check the return signal.  By checking both the "on" and "off"
> >period you can discriminate between a reflection, noise and other
> >illuminators. I.e. someone else's (cough, sumo, cough) robot...  This
> >is used on Cherry Blossom, my mini-sumo and it works really well
> >except that Cherry Blossom doesn't use all the information correctly.
> >
> >Synchronous detection is the how the Sharp GP2DXX series work in a
> >wide variety of lighting situations.  Using a photo detector, or
> >measuring their current draw, you can find out that they put out 11
> >pulses over 40-50 ms before updating the results (digital with the
> >'02, analog with the '12).
> >
> >----
> >Larry Barello
> >www.barello.net
> >
> >----- Original Message -----
> >From: "Kenneth Maxon" <kmaxon@...>
> >>
> >>     I had further thoughts about Rich's article on Smarter Infrared
> >> Proximity Detectors and thought it might be worth a discussion
> >thread which
> >> could refine the idea further.
> >>     Rich's particular noise source mentioned in the article was that
> >> interference coming from fluorescent lights.  His method to handle
> >this
> >> seems quite reasonable, and I propose taking it a step further with
> >a
> >> synthetic PLL.  Since the noise source is highly cyclic wouldn't it
> >make
> >> further sense that the system could build up a pattern of high error
> >times
> >> Vs non erroring times and use this to implement a "blanking
> >interval".
> >...
> >
> >
> >
> >
> >
> >To unsubscribe from this group, send an email to:
> >SeattleRobotics-unsubscribe@egroups.com
> >
> >
> >
> >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
> >
> >
>
>
>
> To unsubscribe from this group, send an email to:
> SeattleRobotics-unsubscribe@egroups.com
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>

Hi all,
I have already posted this to the PIClist so apologies to those that see this
twice. I am posting again here as I didn't get much response to the hardware
part of my question...

I am (hopefully) getting close to the end of my first PIC project! I have a
couple of questions regarding hardware and software design. My project consists
of a bit banged serial port, timer, two encoder counters, and psuedo PWM to
drive two modified hobby servos. This is all done on a 16F84.

From reading this list (PIClist) I understand it is good practice to keep
interrupt service routines short, and use flags which are polled in the main
loop. I am thinking about using this method for the timer, and the serial port.
The code would look something like:

main()
{
     while (1)
     {
     if (timer_flag)
         do something
     }
}

interrupt void isr()
{
     if interrupt cause by timer
         set timer_flag = 1;
}

and the same for the serial i/o...  is this good coding style for PIC's?

Secondly, if this is the solution I end up using then I am probably going to
want to tie at least three incoming lines to the RB0/INT pin (two encoders and
the Rx line for the serial port). How would I multiplex (is that the right
word??) these lines togeather? What component(s) would I use to do this?

I am thinking that every time an interrupt occured on RB0 I could just check the
values of the other i/o pins to see what caused the interrupt.

Sorry for the long winded e-mail, turns out this project was a little more
involved than I first thought it would be ;-)

Thanks very much for any advice,
kind regards,
James Fitzsimons



[Non-text portions of this message have been removed]

I have updated my web page again.  :)
www.coldfirehq.com

I have added a review of a dual axis clinometer, or for those who needed a
translation: an angle sensor.
It is fairly inexpensive and it is a cool addition to a sensor suite on our
robots.
It is in the reviews section.

I have also added some Coldfire related info for those that may be
interested in that.

Thanks,

Matt Minnis



"Pinky, you've left the lens cap of your mind on again." - The Brain
=========================================================
Preferred Resources          (314) 567-7600 phone
701 Emerson rd.              (314) 993-6699 fax
Suite 475                      mminnis@...
St. Louis, MO
63141
=========================================================


************************************************************************
* Tracking #: B9BA64AFC815D6119B900050041A803062954AB1
*
************************************************************************

The date for this year's RoboFair was just sent to me:

http://www.robofair.org/

Doug

We would like to remind you of this upcoming event.

Monday Night Chat

Date: Monday, February 4, 2002
Time: 7:00PM - 9:00PM PST (GMT-08:00)

Monday Night Chat happens every Monday at the SRS. Come ask
questions or offer advice live.

Directions:

The chat requires that you use an Internet Relay Chat (IRC)
program. Details on finding one are below.

For you experts, the chat is held on us.chatjunkies.org in the
#SeattleRobotics group.

For Windows users:

See the SRS website at

http://www.seattlerobotics.org/contact.html#Monday

Most if not all of the industrial quality photoelectric sensors use the
double modulation approach, with an IR filter.  This makes them very
reliable.  I have built hundreds of machines that use these with out any
problems.  For an assembly line that has a million bottles a week going down
it if the sensors are not very reliable there is broken glass everywhere.

The bad news is that these sensors are fairly expensive, $50 to $200.  But
that is mostly due to having solid stain less steel housings, sealed against
everything, and having electronics that can work in very hot and very cold
environments, etc.

But if you made you own it could be done cheaply.

William Crolley


----- Original Message -----
From: Pete Miles <petem@...>
To: <SeattleRobotics@yahoogroups.com>
Sent: Monday, February 04, 2002 11:30 AM
Subject: Re: [SeattleRobotics] Thoughts on an encoder article.


> My experience with the IR sensors is that most people use them
incorrectly,
> including me.
>
> If you read the datasheets for the IR receivers, the signals must be two
> different signals.  The first signal is 40 kHz (depends on when IR
Receiver
> you use), the second signal is a square wave at 1667 to 2500 Hz.  When the
> second signal is high, the IR must be modulated at 40 kHz.  Most people
> forget about the second frequency.  This improves the reliability.
>
> Second, use a sensor that has a plastic shield the blocks visible light.
> The Panasonic ones that Digikey sells does this.  I have circuits that
work
> under direct sunlight.
>
> The main problem about IR reflective sensors is that they are specular
> sensors.  When the IR hits an object, it doesn't neccessarily bounce
> straight back to the receiver.  It bounces some other direction.  Pure
> physics tells you that this will happen.
>
> One way to get around this problem is to use very high intensity IR LEDs.
> This works a whole lot better, but there is a drawback, it starts picking
up
> reflections from objects on the other side of the room.  So there has to
be
> some trade off when selecting the intensity of the IR LEDs.
>
> I have heard rumors that the Japanese use a IR sensor that is extremely
> accurate for sumo applications.  I have also heard that these sensors cost
> $120 each.  I have no idea what they are, but I would love to get my hands
> on one.
>
> I think Ultrasonic sensors would work better than the IR reflecticve
> sensors, but I personally have not used them.
>
> I think the best sensors would be Kens Laser Ranging systems.  It probably
> will be too complicated for a mini sumo, but it should work for a 3 kg
sumo,
> or any other type of robot.
>
> Pete
> petem@...
>
> ----- Original Message -----
> From: "Doug Kelley" <doug.kelley@...>
> To: <SeattleRobotics@yahoogroups.com>
> Sent: Sunday, February 03, 2002 10:07 AM
> Subject: Re: [SeattleRobotics] Thoughts on an encoder article.
>
>
> > It seems IR is a little unreliable for sumos.  Is anyone doing anything
> with
> > sonar?  It's slow, but might work well for minis.  The little one that
> Acroname
> > sells seems like it would be ideal.  It's low current and (I think) has
a
> range
> > of about one meter.
> >
> > I'm not suggesting sonar as the sole sensor but it might complement IR
> nicely
> > since it's immune to light and detects objects over a relatively wide
> beam.
> >
> > Doug
> >
> > lbarello@... writes:
> > >You could implement synchronous detection.  I.e. gate the illuminator
> > >and check the return signal.  By checking both the "on" and "off"
> > >period you can discriminate between a reflection, noise and other
> > >illuminators. I.e. someone else's (cough, sumo, cough) robot...  This
> > >is used on Cherry Blossom, my mini-sumo and it works really well
> > >except that Cherry Blossom doesn't use all the information correctly.
> > >
> > >Synchronous detection is the how the Sharp GP2DXX series work in a
> > >wide variety of lighting situations.  Using a photo detector, or
> > >measuring their current draw, you can find out that they put out 11
> > >pulses over 40-50 ms before updating the results (digital with the
> > >'02, analog with the '12).
> > >
> > >----
> > >Larry Barello
> > >www.barello.net
> > >
> > >----- Original Message -----
> > >From: "Kenneth Maxon" <kmaxon@...>
> > >>
> > >>     I had further thoughts about Rich's article on Smarter Infrared
> > >> Proximity Detectors and thought it might be worth a discussion
> > >thread which
> > >> could refine the idea further.
> > >>     Rich's particular noise source mentioned in the article was that
> > >> interference coming from fluorescent lights.  His method to handle
> > >this
> > >> seems quite reasonable, and I propose taking it a step further with
> > >a
> > >> synthetic PLL.  Since the noise source is highly cyclic wouldn't it
> > >make
> > >> further sense that the system could build up a pattern of high error
> > >times
> > >> Vs non erroring times and use this to implement a "blanking
> > >interval".
> > >...
> > >
> > >
> > >
> > >
> > >
> > >To unsubscribe from this group, send an email to:
> > >SeattleRobotics-unsubscribe@egroups.com
> > >
> > >
> > >
> > >Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
> > >
> > >
> >
> >
> >
> > To unsubscribe from this group, send an email to:
> > SeattleRobotics-unsubscribe@egroups.com
> >
> >
> >
> > Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
> >
> >
> >
>
>
> To unsubscribe from this group, send an email to:
> SeattleRobotics-unsubscribe@egroups.com
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>

Here are a couple of links
http://home.earthlink.net/~y2kbc/Electronics/BasicStamp/Coilread.gif
http://home.earthlink.net/~y2kbc/Electronics/BasicStamp/LVDT.gif

Craig


> Message: 1
>    Date: Sun, 3 Feb 2002 12:50:58 -0800
>    From: "Bob Dyer" <bd@...>
> Subject: Linear Displacement Transducer
>
> Has anyone seen a linear displacement transducer that's not too expensive
> with at least 6 inches of travel? A slide pot would be ideal, (low friction,
> high resolution and cheap) but the longest one I've seen so far (Digi-Key)
> is 4 inches. Thanks.
>
> Bob
>
> -------------------------
> Consider Carefully...  Act Boldly!
>

HI all,

I'm working on a robot that will use a laptop as the brains. I'm planning on
using some 1/4 scale servos for the drive motors. My concern is that the weight
of the laptop and some gel cells is going to quickly destroy the servo gears if
I mount the wheels right on the control horn. The design is to have differential
steering with a trailing caster wheel. Should I be concerned about the servos?
If so I'll drive an axle that supports the weight.

Also, what is the thread on a servo horn screw for a Hitec servo? It looks like
about a 4-20 if there were such a beast. Is it metric?

Rud Merriam
K5RUD




[Non-text portions of this message have been removed]

Hi Donovan,

At 19:24 2/3/02 -0800, you wrote:
>This may sound wierd- any Applewriter II printers
>around? The old dot matrix ones have wonderful 30oz-in
>1.8 degree per step 6 wire stepper motors.
>
>I connected one up and measured the torque. Since then
>I've collected a bunch of the printers from people
>throwing them out and picked up from thrift stores
>cheap and torn the printers apart.
>
>The printer also contains a 28Vac 2 or 3A low profile
>transformer.
>
>Steve Greenfield
>
>--- Donovan Parks <dparks@...> wrote:
> > Hello,
> >
> > I'm in need of a stepper motor with a small step
> > size (around 2 degree).
> > I'm looking for a source for such a stepper motor -
> > preferably Canadian. :-)

Vancouver Island Robotics got some apple dot matrix, and bubble jet
printers donated to the cause, I posted these a while ago to our
list...  Dunno if they're the exact ones Steve is talking about, but it
might be worth taking a peek.  They're taking up a bunch of space in my
garage right now, let me know if you're interested.

Steve
steve@...

You might check out http://www.servocity.com for pre (HiTec and Futaba)
splined servo horn gears and http://www.servolink.com/ for similar gears for
normal shafts. That way you could chain drive your wheels that are mounted
on some type of pillow blocks and mount your servos where-ever needed

David

----- Original Message -----
From: "Rud Merriam" <rmerriam@...>
To: <seattleRobotics@yahoogroups.com>
Sent: Monday, February 04, 2002 10:56 PM
Subject: [SeattleRobotics] Servo Advice


> HI all,
>
> I'm working on a robot that will use a laptop as the brains. I'm planning
on using some 1/4 scale servos for the drive motors. My concern is that the
weight of the laptop and some gel cells is going to quickly destroy the
servo gears if I mount the wheels right on the control horn. The design is
to have differential steering with a trailing caster wheel. Should I be
concerned about the servos? If so I'll drive an axle that supports the
weight.
>
> Also, what is the thread on a servo horn screw for a Hitec servo? It looks
like about a 4-20 if there were such a beast. Is it metric?
>
> Rud Merriam
> K5RUD
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
> To unsubscribe from this group, send an email to:
> SeattleRobotics-unsubscribe@egroups.com
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>


_________________________________________________________
Do You Yahoo!?
Get your free @yahoo.com address at http://mail.yahoo.com

--- In SeattleRobotics@y..., "David Peterson" <robologist@y...> wrote:
> You might check out http://www.servocity.com for pre (HiTec and
Futaba)> splined servo horn gears
.........


Hi, while looking around the servocity site, I noticed their servo
savers - basically spring-loaded servo horns:

http://www.servocity.com/Products/Servo_Savers/servo_savers.html

Anyone know how much tension there is in these springs - and how much
give? I am wondering, if you use these to directly mount the legs on
a small walker, 1# weight or so, whether the compliance would be
overly much, and the gaits might have excessive wobble.

?????????

thanks,
- dan michaels
www.oricomtech.com
=============================

James,
	 That's quite an ambitious first PIC project!  As for interrupts, you should
be able to do most, if not all, the necessary processing for the interrupt
within the body of the interrupt service routine (ISR).  As a rule of thumb,
if you don't have any loops within the ISR, then you probably can just put
all that code into the ISR, without resorting to flags.  The definitive
answer would require an analysis of all the interrupt sources, the amount of
processing required to service those interrupts, and the maximum acceptable
interrupt latency.
	 Have you considered using the 16F84's port B interrupt on change feature?
That could be an easy way to gain up to four input lines capable of
generating an interrupt.  What I would do in your case would be to connect
the Rx line to RB0/INT, and then attach the encoders to port B 4 through 7.
That way, every time the encoder state changed, you can compare the current
encoder state to the previous encoder state, and from there determine which
direction the shaft is turning.

David Smith


-----Original Message-----
From: James Fitzsimons [mailto:jamesfit@...]
Sent: Monday, February 04, 2002 12:55 PM
To: srs
Subject: [SeattleRobotics] PIC questions


Hi all,
I have already posted this to the PIClist so apologies to those that see
this twice. I am posting again here as I didn't get much response to the
hardware part of my question...

I am (hopefully) getting close to the end of my first PIC project! I have a
couple of questions regarding hardware and software design. My project
consists of a bit banged serial port, timer, two encoder counters, and
psuedo PWM to drive two modified hobby servos. This is all done on a 16F84.

From reading this list (PIClist) I understand it is good practice to keep
interrupt service routines short, and use flags which are polled in the main
loop. I am thinking about using this method for the timer, and the serial
port. The code would look something like:

main()
{
     while (1)
     {
     if (timer_flag)
         do something
     }
}

interrupt void isr()
{
     if interrupt cause by timer
         set timer_flag = 1;
}

and the same for the serial i/o...  is this good coding style for PIC's?

Secondly, if this is the solution I end up using then I am probably going to
want to tie at least three incoming lines to the RB0/INT pin (two encoders
and the Rx line for the serial port). How would I multiplex (is that the
right word??) these lines togeather? What component(s) would I use to do
this?

I am thinking that every time an interrupt occured on RB0 I could just check
the values of the other i/o pins to see what caused the interrupt.

Sorry for the long winded e-mail, turns out this project was a little more
involved than I first thought it would be ;-)

Thanks very much for any advice,
kind regards,
James Fitzsimons



[Non-text portions of this message have been removed]


To unsubscribe from this group, send an email to:
SeattleRobotics-unsubscribe@egroups.com



Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

Hi all,
just a quick email to say thanks to those that responded to my post. I
definately have some ideas to try out now!

Kind regards,
James Fitzsimons

This month's meeting will be located in two places.  First, we'll hold our
regular meeting at its normal time and new location (J-314).  Evolution
Robotics will be there with a demonstration of their new robot platform.  At
11:30, we'll move to Roosevelt High School Gymnasium for the FIRST pre-ship
event.  That should run until 4:30.  Maps will be available at the meeting.

Robothon T-shirts will also be for sale.  They are $20 and you'll want to get
yours early; we only printed 150 this year.  Also, by purchasing T-shirts
before Robothon, you'll help the club financially.  We have to pay a commission
to Seattle Center on all T-shirts sold at Robothon.

Doug

Hello, I'm new here. Do you have to be a member of the
Seattle Robotics Society to attend?

And the regular time is? What day? Where and what is
J-314?

Steve Greenfield

--- Doug Kelley <doug.kelley@...> wrote:
> This month's meeting will be located in two places.
> First, we'll hold our
> regular meeting at its normal time and new location
> (J-314).  Evolution
> Robotics will be there with a demonstration of their
> new robot platform


__________________________________________________
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Anyone can come to the meeting.  It starts at 10:00 am.  J-314 is Building
"J" room "314"
Direction to get there is found here:
http://www.seattlerobotics.org/meetings.html

See you at the meeting

Pete
petem@...

----- Original Message -----
From: "Steve Greenfield" <polymorph@...>
To: "SeattleRobotics Mailing List" <seattlerobotics@yahoogroups.com>
Sent: Wednesday, February 06, 2002 1:00 PM
Subject: Re: [SeattleRobotics] February Meeting


> Hello, I'm new here. Do you have to be a member of the
> Seattle Robotics Society to attend?
>
> And the regular time is? What day? Where and what is
> J-314?
>
> Steve Greenfield
>
> --- Doug Kelley <doug.kelley@...> wrote:
> > This month's meeting will be located in two places.
> > First, we'll hold our
> > regular meeting at its normal time and new location
> > (J-314).  Evolution
> > Robotics will be there with a demonstration of their
> > new robot platform
>
>
> __________________________________________________
> Do You Yahoo!?
> Send FREE Valentine eCards with Yahoo! Greetings!
> http://greetings.yahoo.com
>
> To unsubscribe from this group, send an email to:
> SeattleRobotics-unsubscribe@egroups.com
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>

I will be bringing the mini-sumo ring to the FIRST meeting.  So bring your
mini sumo robots to the FIRST meeting to show off to the FIRST crowd.

Pete
petem@...

Is there anyone in the Phoenix Arizona area interested in forming a
robotics group to meet regularly?  I am involved with a Amatuer Radio
high altitude balloon group www.ansr.org and a cross-group team would
provide very interesting projects.  Atmospheric measurements,
telemetry, radio links and recovery vehicles (airplanes and guided
parachutes).  Ever want to know what happens to lithium batteries at
100,000 ft?  What happens to a package after falling 100,000 ft?

Mr. Lunt do you know of anyone left here in the desert?

David Boswell

At 9:01 AM 2/7/02, boswell85203 wrote:
>Is there anyone in the Phoenix Arizona area interested in forming a
>robotics group to meet regularly?  I am involved with a Amatuer Radio
>high altitude balloon group www.ansr.org and a cross-group team would
>provide very interesting projects.  Atmospheric measurements,
>telemetry, radio links and recovery vehicles (airplanes and guided
>parachutes).  Ever want to know what happens to lithium batteries at
>100,000 ft?  What happens to a package after falling 100,000 ft?
>
>Mr. Lunt do you know of anyone left here in the desert?
>
>David Boswell
>


This is the latest information I have on the robotics club in Phoenix:


City and State: Phoenix, Arizona
Group name:     Phoenix Area Robotics eXperimenters (PAReX)
Contact:        Mike Reiner, president
Email:          k6zwc@...
URL:            http://www.web-robots.com/parex,
                 http://www.botbash.com
Meetings:       1st Friday of the month, Location info on web site


-Robert Nansel

I couldn't get some links to work, but this one just popped up something
that might be what you want:

http://www.parex.org/

Here is a few pictures of a High School event they held last year - some
neat looking 'bots in this one:

http://www.parex.org/hamiltonhigh2000.shtml

Dan
-----Original Message-----
From: bnansel@... [mailto:bnansel@...]
Sent: Thursday, February 07, 2002 8:35 AM
To: boswell85203; SeattleRobotics@yahoogroups.com
Subject: [SeattleRobotics] Re: Phoenix Arizona?


At 9:01 AM 2/7/02, boswell85203 wrote:
>Is there anyone in the Phoenix Arizona area interested in forming a
>robotics group to meet regularly?  I am involved with a Amatuer Radio
>high altitude balloon group www.ansr.org and a cross-group team would
>provide very interesting projects.  Atmospheric measurements,
>telemetry, radio links and recovery vehicles (airplanes and guided
>parachutes).  Ever want to know what happens to lithium batteries at
>100,000 ft?  What happens to a package after falling 100,000 ft?
>
>Mr. Lunt do you know of anyone left here in the desert?
>
>David Boswell
>


This is the latest information I have on the robotics club in Phoenix:


City and State: Phoenix, Arizona
Group name:     Phoenix Area Robotics eXperimenters (PAReX)
Contact:        Mike Reiner, president
Email:          k6zwc@...
URL:            http://www.web-robots.com/parex,
                 http://www.botbash.com
Meetings:       1st Friday of the month, Location info on web site


-Robert Nansel



To unsubscribe from this group, send an email to:
SeattleRobotics-unsubscribe@egroups.com



Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

Cool, I didn't know this. Past Nuts N Volts articles
about the Basic Stamp are up on the Parallax website.

http://www.parallaxinc.com/html_files/resources/nutsvolts.htm

Steve Greenfield

=====
Steve Greenfield               // Digital photo scanning, retouching,
Polymorph Digital Photography // and photomorphing to your specs.
253/318-2473 voice           // We use the best little computer in
polymorph@...     // the world, the Amiga!
http://www.polyphoto.com/  // Based in Tacoma, WA, USA

__________________________________________________
Do You Yahoo!?
Send FREE Valentine eCards with Yahoo! Greetings!
http://greetings.yahoo.com

I am located in Phoenix (Tempe).  I experiment with robots
and I'm also a radio amateur.  I have attended ANSR meetings
and receive their email.  Unfortunately, I have been too busy to
participate.

PAREX is a local robot club, but when I attended their meetings
some time ago, they were dominated by one person or so (not
the club president) and concerned only BotBash, their version
BattleBots.

Feel free to view my robot or contact me:
   http://www.qsl.net/k7on/robotics/index.htm

At 02:01 PM 2/7/02 +0000, you wrote:
>Is there anyone in the Phoenix Arizona area interested in forming a
>robotics group to meet regularly?  I am involved with a Amatuer Radio
>high altitude balloon group www.ansr.org and a cross-group team would
>provide very interesting projects.  Atmospheric measurements,
>telemetry, radio links and recovery vehicles (airplanes and guided
>parachutes).  Ever want to know what happens to lithium batteries at
>100,000 ft?  What happens to a package after falling 100,000 ft?
>
>Mr. Lunt do you know of anyone left here in the desert?
>
>David Boswell

--
k7on@...  >or<  http://www.qsl.net/k7on/
--

I did decide to mount the wheels on an axle using ServoCity chain and
sprokets to drive them.

I'm using the Ferrettronics serial servo controller and digital input chip.
The main sensor input will be a USB web cam.

Rud Merriam
K5RUD


----- Original Message -----
From: "Karim Virani" <karim@...>
To: "'Rud Merriam'" <rmerriam@...>; <seattleRobotics@yahoogroups.com>
Sent: Thursday, February 07, 2002 8:03 PM
Subject: RE: [SeattleRobotics] Servo Advice


> Hi Rud,
>
> I agree with David, mount the wheels on an axle.
>
> What are you doing for I/O?.  Are you using the parallel port, or have you
> found a solution that offers more I/O, both analog and digital.  My dream
> has been to find a product that provides 16 or more digital pins and 4 or
> more 10-bit A/D pins that could connect to a laptop via USB.  All for a
> modest cost, of course.  Have you found anything like that.  The only
> products I've seen that come close are for lab instrumentation and tend to
> be a bit pricey.
>
> Karim
>
> -----Original Message-----
> From: Rud Merriam [mailto:rmerriam@...]
> Sent: Monday, February 04, 2002 10:56 PM
> To: seattleRobotics@yahoogroups.com
> Subject: [SeattleRobotics] Servo Advice
>
>
> HI all,
>
> I'm working on a robot that will use a laptop as the brains. I'm planning
on
> using some 1/4 scale servos for the drive motors. My concern is that the
> weight of the laptop and some gel cells is going to quickly destroy the
> servo gears if I mount the wheels right on the control horn. The design is
> to have differential steering with a trailing caster wheel. Should I be
> concerned about the servos? If so I'll drive an axle that supports the
> weight.
>
> Also, what is the thread on a servo horn screw for a Hitec servo? It looks
> like about a 4-20 if there were such a beast. Is it metric?
>
> Rud Merriam
> K5RUD
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
> To unsubscribe from this group, send an email to:
> SeattleRobotics-unsubscribe@egroups.com
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
>
>

Hi,

I use the bb2 board today with 32k ram. My question is if it is possible to
change this to a EEprom (I only need about 8k of memory), flash or battery
backup without to much modifications.

Ørjan


e-mail : orjan_tveit@...



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hi!
nice to see that  u r also third year engg. student
u r from which country
i am from delhi, india
would u like to have friendship with me.
i am keen to have u one of mine friend
hope we wud be helpful to each other
i am doing research in IIT delhi
wanna construct one fire fighting robot
i got solution to last problem
thanks for mailing
bye
ankur
mittalankur@...


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