Compass Choice
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Posts: 46,084
For those that are using a compass with their robot, what compass are
you using ?
I've looked at the Devantech CMPS03 and the Vector 2x. My goal is to
use the compass to guide the mower robot in a straight path.
I don't actually care if the direction is accurate in regards to
mounting it near motors - I figure the compass will be off, but if I
keep the
robot pointed in that direction it should still be in a straight line.
Any thoughts are welcome.
[noparse][[/noparse]Non-text portions of this message have been removed]
you using ?
I've looked at the Devantech CMPS03 and the Vector 2x. My goal is to
use the compass to guide the mower robot in a straight path.
I don't actually care if the direction is accurate in regards to
mounting it near motors - I figure the compass will be off, but if I
keep the
robot pointed in that direction it should still be in a straight line.
Any thoughts are welcome.
[noparse][[/noparse]Non-text portions of this message have been removed]
Comments
What I did was mount it a few inches above everything using a plastic
post. I never had any problems and the output from the CMPS01 always
matched a reference compass.
-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office
Original Message
From: Bryan Smith [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=hNod0NpSN7zdr9tWF94QzC5fKRROPjrfrrdTDNgHqyW1BUltPAEZQ5kZNwK7IkpnCoHadzOXmWqydw]bsmith@w...[/url
Sent: Thursday, October 23, 2003 3:06 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Compass Choice
Importance: High
For those that are using a compass with their robot, what compass are
you using ?
I've looked at the Devantech CMPS03 and the Vector 2x. My goal is to
use the compass to guide the mower robot in a straight path. I don't
actually care if the direction is accurate in regards to mounting it
near motors - I figure the compass will be off, but if I keep the robot
pointed in that direction it should still be in a straight line. Any
thoughts are welcome.
[noparse][[/noparse]Non-text portions of this message have been removed]
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
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Just how accurate does this need to be?
I'd stay away from using a compass if you need anything better than 30
degree precision. Try going over your yard at 1ft. or so above the grass,
and see what kind of precision and accuracy you get with a normal compass.
I'd say you'd frequently get variations of 10-15 degrees, and occasionally
even greater variance. Compasses work best when they're far from the ground,
away from man-made or other ferrous obstructions (houses, gas lines, cars,
metal edging, sprinkler heads, etc.) Add to this the electromagnetic chaos
you get in close proximity to a two-stroke motor, and I'd say you won't get
anything better than 30-50 degree precision, and terrible accuracy. The
problem with running compasses near motors and electronics is not one of
heading offset (i.e., it won't always be off by 10, 15, or x degrees), but
rather one of erratic, unreliable operation.
IIRC, the compasses you mentioned aren't cheap (>$40?), so you may be better
off going with an inexpensive GPS unit. Many OEM units are available
nowadays with 15m accuracy for <$120. I think several (try Trimble
[noparse][[/noparse]www.trimble.com] and u-blox [noparse][[/noparse]www.ublox.com]) even are WAAS enabled, giving
you fairly consistent 3m accuracy. While you won't necessarily get the same
heading resolution or update rate that you can get with a compass, the data
you do get will be consistently more accurate and precise. The main problem
I think you'll run into with GPS is while maneuvering in tight spots less
than the radius of uncertainty (is that the correct term?). How big is your
yard?
One alternate approach might be to mount the compass a couple of feet from
the mower on a pole, much like a conventional mower handle to escape the EMF
disturbances of the motor, and to simply manually drive the mower around the
lawn to make an electromagnetic "map" of your yard. Through odometry, you
can determine where you are in the yard (distance from the starting point),
and maybe even a rough heading estimate (although the slipperiness of grass
may preclude this option). You can then have a table of magnetic corrections
for each region or point in the yard. The issue you may face here is going
beyond the processing and speed capabilities of the Stamp. I would think
this would get you to at least 5 degrees or so of precision (and maybe even
decent accuracy). Combined with a backup collision/accident avoidance system
(bumpers, buried wire, ultrasonic range detection, whatever floats your
boat) this would probably be adequate to get a decent-looking lawn.
Any more questions? I'm full of answers! (I never said correct ones :O) !)
- Robert
Original Message
From: "Bryan Smith" <bsmith@w...>
To: <basicstamps@yahoogroups.com>
Sent: Thursday, October 23, 2003 2:06 PM
Subject: [noparse][[/noparse]basicstamps] Compass Choice
> For those that are using a compass with their robot, what compass are
> you using ?
>
> I've looked at the Devantech CMPS03 and the Vector 2x. My goal is to
> use the compass to guide the mower robot in a straight path.
> I don't actually care if the direction is accurate in regards to
> mounting it near motors - I figure the compass will be off, but if I
> keep the
> robot pointed in that direction it should still be in a straight line.
> Any thoughts are welcome.
>
>
>
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
code for interfacing them with a Stamp. Would I use an ADC as this
person has done ?
( http://www.angelfire.com/super/lego/compass/ )
Original Message
From: Jon Williams [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=3c1yvxVhE0QemZtmNYW4Qipc06SXbhIBQLUwH5UfeR6zXBBqhSWqGRpHTmyqOs2DIHt4V_iHTSAR_jliYA]jwilliams@p...[/url
Sent: Thursday, October 23, 2003 3:36 PM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] Compass Choice
I've used the CMPS03 on a BOE-Bot (using BASIC Stamps and the Javelin).
What I did was mount it a few inches above everything using a plastic
post. I never had any problems and the output from the CMPS01 always
matched a reference compass.
-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office
Original Message
From: Bryan Smith [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=kEgWG2X7EvLfnmdrV1P3H-geG54JdiWd1rxhH4cA56x5X_1vxHBJkhtzDIcZAAeFRmdbHbhAou7hHMcL]bsmith@w...[/url
Sent: Thursday, October 23, 2003 3:06 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Compass Choice
Importance: High
For those that are using a compass with their robot, what compass are
you using ?
I've looked at the Devantech CMPS03 and the Vector 2x. My goal is to
use the compass to guide the mower robot in a straight path. I don't
actually care if the direction is accurate in regards to mounting it
near motors - I figure the compass will be off, but if I keep the robot
pointed in that direction it should still be in a straight line. Any
thoughts are welcome.
[noparse][[/noparse]Non-text portions of this message have been removed]
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full of bumps and dips. GPS is too expensive for me ( $40 - $50 is my
limit ). I've also thought about using a piezo gyro, but I haven't
explored it much though. I've also thought about scrapping the compass
idea and do some kind of sensor that senses the edge of unmowed grass -
but I also have patches of dirt, clover, and dead grass. So I think the
compass would be easier.
Thank you for your ideas
Original Message
From: Robert Ussery [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=pJ8nGsuu8YowOLZjTZKG0Y-LwnM-1FRdwV7kDAaL-5CGzBWBov6FbVm75d8l8EL3PQ0udrJh-Nurtd15]uavscience@f...[/url
Sent: Thursday, October 23, 2003 4:03 PM
To: basicstamps@yahoogroups.com
Subject: Re: [noparse][[/noparse]basicstamps] Compass Choice
Bryan -
Just how accurate does this need to be?
I'd stay away from using a compass if you need anything better than 30
degree precision. Try going over your yard at 1ft. or so above the
grass, and see what kind of precision and accuracy you get with a normal
compass. I'd say you'd frequently get variations of 10-15 degrees, and
occasionally even greater variance. Compasses work best when they're far
from the ground, away from man-made or other ferrous obstructions
(houses, gas lines, cars, metal edging, sprinkler heads, etc.) Add to
this the electromagnetic chaos you get in close proximity to a
two-stroke motor, and I'd say you won't get anything better than 30-50
degree precision, and terrible accuracy. The problem with running
compasses near motors and electronics is not one of heading offset
(i.e., it won't always be off by 10, 15, or x degrees), but rather one
of erratic, unreliable operation. IIRC, the compasses you mentioned
aren't cheap (>$40?), so you may be better off going with an inexpensive
GPS unit. Many OEM units are available nowadays with 15m accuracy for
<$120. I think several (try Trimble [noparse][[/noparse]www.trimble.com] and u-blox
[noparse][[/noparse]www.ublox.com]) even are WAAS enabled, giving you fairly consistent 3m
accuracy. While you won't necessarily get the same heading resolution or
update rate that you can get with a compass, the data you do get will be
consistently more accurate and precise. The main problem I think you'll
run into with GPS is while maneuvering in tight spots less than the
radius of uncertainty (is that the correct term?). How big is your yard?
One alternate approach might be to mount the compass a couple of feet
from the mower on a pole, much like a conventional mower handle to
escape the EMF disturbances of the motor, and to simply manually drive
the mower around the lawn to make an electromagnetic "map" of your yard.
Through odometry, you can determine where you are in the yard (distance
from the starting point), and maybe even a rough heading estimate
(although the slipperiness of grass may preclude this option). You can
then have a table of magnetic corrections for each region or point in
the yard. The issue you may face here is going beyond the processing and
speed capabilities of the Stamp. I would think this would get you to at
least 5 degrees or so of precision (and maybe even decent accuracy).
Combined with a backup collision/accident avoidance system (bumpers,
buried wire, ultrasonic range detection, whatever floats your
boat) this would probably be adequate to get a decent-looking lawn. Any
more questions? I'm full of answers! (I never said correct ones :O) !)
- Robert
Original Message
From: "Bryan Smith" <bsmith@w...>
To: <basicstamps@yahoogroups.com>
Sent: Thursday, October 23, 2003 2:06 PM
Subject: [noparse][[/noparse]basicstamps] Compass Choice
> For those that are using a compass with their robot, what compass are
> you using ?
>
> I've looked at the Devantech CMPS03 and the Vector 2x. My goal is to
> use the compass to guide the mower robot in a straight path. I don't
> actually care if the direction is accurate in regards to mounting it
> near motors - I figure the compass will be off, but if I keep the
> robot pointed in that direction it should still be in a straight line.
> Any thoughts are welcome.
>
>
>
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject
> and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
>
>
To UNSUBSCRIBE, just send mail to:
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from the same email address that you subscribed. Text in the Subject
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>I'm hoping that it will be fairly accurate. It is a small yard - and
>full of bumps and dips. GPS is too expensive for me ( $40 - $50 is my
>limit ). I've also thought about using a piezo gyro, but I haven't
>explored it much though. I've also thought about scrapping the compass
>idea and do some kind of sensor that senses the edge of unmowed grass -
>but I also have patches of dirt, clover, and dead grass. So I think the
>compass would be easier.
>
>Thank you for your ideas
Bryan -
The robotic mowers which you see for sale generally use a buried wire system.
The mower follows the buried wire and stays inside its bounds. That way you
can set the area to be mowed. This is the same type of principle used by
the devices which keep a dog within an un-fenced area.
Bruce Bates
>
Original Message
>From: Robert Ussery [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=0oodFOSFNS9odvMX1AZ_g3dgsMzKBn2K1ftwTN3hq9y_uhLQeDZHIpWVSSzNxe7EV4Xn_WPSzguhiLpGXg]uavscience@f...[/url
>Sent: Thursday, October 23, 2003 4:03 PM
>To: basicstamps@yahoogroups.com
>Subject: Re: [noparse][[/noparse]basicstamps] Compass Choice
>
>
>Bryan -
>Just how accurate does this need to be?
>I'd stay away from using a compass if you need anything better than 30
>degree precision. Try going over your yard at 1ft. or so above the
>grass, and see what kind of precision and accuracy you get with a normal
>compass. I'd say you'd frequently get variations of 10-15 degrees, and
>occasionally even greater variance. Compasses work best when they're far
>from the ground, away from man-made or other ferrous obstructions
>(houses, gas lines, cars, metal edging, sprinkler heads, etc.) Add to
>this the electromagnetic chaos you get in close proximity to a
>two-stroke motor, and I'd say you won't get anything better than 30-50
>degree precision, and terrible accuracy. The problem with running
>compasses near motors and electronics is not one of heading offset
>(i.e., it won't always be off by 10, 15, or x degrees), but rather one
>of erratic, unreliable operation. IIRC, the compasses you mentioned
>aren't cheap (>$40?), so you may be better off going with an inexpensive
>GPS unit. Many OEM units are available nowadays with 15m accuracy for
><$120. I think several (try Trimble [noparse][[/noparse]www.trimble.com] and u-blox
>[noparse][[/noparse]www.ublox.com]) even are WAAS enabled, giving you fairly consistent 3m
>accuracy. While you won't necessarily get the same heading resolution or
>update rate that you can get with a compass, the data you do get will be
>consistently more accurate and precise. The main problem I think you'll
>run into with GPS is while maneuvering in tight spots less than the
>radius of uncertainty (is that the correct term?). How big is your yard?
>One alternate approach might be to mount the compass a couple of feet
>from the mower on a pole, much like a conventional mower handle to
>escape the EMF disturbances of the motor, and to simply manually drive
>the mower around the lawn to make an electromagnetic "map" of your yard.
>Through odometry, you can determine where you are in the yard (distance
>from the starting point), and maybe even a rough heading estimate
>(although the slipperiness of grass may preclude this option). You can
>then have a table of magnetic corrections for each region or point in
>the yard. The issue you may face here is going beyond the processing and
>speed capabilities of the Stamp. I would think this would get you to at
>least 5 degrees or so of precision (and maybe even decent accuracy).
>Combined with a backup collision/accident avoidance system (bumpers,
>buried wire, ultrasonic range detection, whatever floats your
>boat) this would probably be adequate to get a decent-looking lawn. Any
>more questions? I'm full of answers! (I never said correct ones :O) !)
>
>- Robert
>
Original Message
>From: "Bryan Smith" <bsmith@w...>
>To: <basicstamps@yahoogroups.com>
>Sent: Thursday, October 23, 2003 2:06 PM
>Subject: [noparse][[/noparse]basicstamps] Compass Choice
>
>
> > For those that are using a compass with their robot, what compass are
> > you using ?
> >
> > I've looked at the Devantech CMPS03 and the Vector 2x. My goal is to
> > use the compass to guide the mower robot in a straight path. I don't
> > actually care if the direction is accurate in regards to mounting it
> > near motors - I figure the compass will be off, but if I keep the
> > robot pointed in that direction it should still be in a straight line.
> > Any thoughts are welcome.
> >
> >
> >
> >
> >
> > [noparse][[/noparse]Non-text portions of this message have been removed]
> >
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@yahoogroups.com
> > from the same email address that you subscribed. Text in the Subject
> > and
>Body of the message will be ignored.
> >
> >
> > Your use of Yahoo! Groups is subject to
> > http://docs.yahoo.com/info/terms/
> >
> >
>
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject
>and Body of the message will be ignored.
>
>
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>http://docs.yahoo.com/info/terms/
>
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject and
>Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
boundry fence. I'm wanting the robot to mow in a straight line - the
ones I've seen mow in random directions. Hence, I was hoping that I
could use a compass for maintaining a straight course.
Original Message
From: Bruce Bates [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=l9rUGuGJSrWoSgVTON_6sGwaZPkzXG0g2OJBgj5-MLxhHAqd-aaaT1grLt2-42G3CQIQMoDy3HLg_KkchlKb]bvbates@u...[/url
Sent: Friday, October 24, 2003 8:28 AM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] Compass Choice
At 08:18 AM 10/24/03 -0500, Bryan Smith wrote:
>I'm hoping that it will be fairly accurate. It is a small yard - and
>full of bumps and dips. GPS is too expensive for me ( $40 - $50 is my
>limit ). I've also thought about using a piezo gyro, but I haven't
>explored it much though. I've also thought about scrapping the compass
>idea and do some kind of sensor that senses the edge of unmowed grass -
>but I also have patches of dirt, clover, and dead grass. So I think
>the compass would be easier.
>
>Thank you for your ideas
Bryan -
The robotic mowers which you see for sale generally use a buried wire
system. The mower follows the buried wire and stays inside its bounds.
That way you
can set the area to be mowed. This is the same type of principle used by
the devices which keep a dog within an un-fenced area.
Bruce Bates
>
Original Message
>From: Robert Ussery [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=bMNeoJUu2vvyv29qQNuGc8jxFkkxJ2JdYXNogCWpMlBrcculYrxdBDrdOb0ohkmo-icWF0M-9L1f6co]uavscience@f...[/url
>Sent: Thursday, October 23, 2003 4:03 PM
>To: basicstamps@yahoogroups.com
>Subject: Re: [noparse][[/noparse]basicstamps] Compass Choice
>
>
>Bryan -
>Just how accurate does this need to be?
>I'd stay away from using a compass if you need anything better than 30
>degree precision. Try going over your yard at 1ft. or so above the
>grass, and see what kind of precision and accuracy you get with a
>normal compass. I'd say you'd frequently get variations of 10-15
>degrees, and occasionally even greater variance. Compasses work best
>when they're far from the ground, away from man-made or other ferrous
>obstructions (houses, gas lines, cars, metal edging, sprinkler heads,
>etc.) Add to this the electromagnetic chaos you get in close proximity
>to a two-stroke motor, and I'd say you won't get anything better than
>30-50 degree precision, and terrible accuracy. The problem with running
>compasses near motors and electronics is not one of heading offset
>(i.e., it won't always be off by 10, 15, or x degrees), but rather one
>of erratic, unreliable operation. IIRC, the compasses you mentioned
>aren't cheap (>$40?), so you may be better off going with an
>inexpensive GPS unit. Many OEM units are available nowadays with 15m
>accuracy for <$120. I think several (try Trimble [noparse][[/noparse]www.trimble.com] and
>u-blox
>[noparse][[/noparse]www.ublox.com]) even are WAAS enabled, giving you fairly consistent 3m
>accuracy. While you won't necessarily get the same heading resolution
or
>update rate that you can get with a compass, the data you do get will
be
>consistently more accurate and precise. The main problem I think you'll
>run into with GPS is while maneuvering in tight spots less than the
>radius of uncertainty (is that the correct term?). How big is your
yard?
>One alternate approach might be to mount the compass a couple of feet
>from the mower on a pole, much like a conventional mower handle to
>escape the EMF disturbances of the motor, and to simply manually drive
>the mower around the lawn to make an electromagnetic "map" of your
yard.
>Through odometry, you can determine where you are in the yard (distance
>from the starting point), and maybe even a rough heading estimate
>(although the slipperiness of grass may preclude this option). You can
>then have a table of magnetic corrections for each region or point in
>the yard. The issue you may face here is going beyond the processing
and
>speed capabilities of the Stamp. I would think this would get you to at
>least 5 degrees or so of precision (and maybe even decent accuracy).
>Combined with a backup collision/accident avoidance system (bumpers,
>buried wire, ultrasonic range detection, whatever floats your
>boat) this would probably be adequate to get a decent-looking lawn. Any
>more questions? I'm full of answers! (I never said correct ones :O) !)
>
>- Robert
>
Original Message
>From: "Bryan Smith" <bsmith@w...>
>To: <basicstamps@yahoogroups.com>
>Sent: Thursday, October 23, 2003 2:06 PM
>Subject: [noparse][[/noparse]basicstamps] Compass Choice
>
>
> > For those that are using a compass with their robot, what compass
> > are you using ?
> >
> > I've looked at the Devantech CMPS03 and the Vector 2x. My goal is
> > to use the compass to guide the mower robot in a straight path. I
> > don't actually care if the direction is accurate in regards to
> > mounting it near motors - I figure the compass will be off, but if I
> > keep the robot pointed in that direction it should still be in a
> > straight line. Any thoughts are welcome.
> >
> >
> >
> >
> >
> > [noparse][[/noparse]Non-text portions of this message have been removed]
> >
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@yahoogroups.com
> > from the same email address that you subscribed. Text in the
> > Subject and
>Body of the message will be ignored.
> >
> >
> > Your use of Yahoo! Groups is subject to
> > http://docs.yahoo.com/info/terms/
> >
> >
>
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject
>and Body of the message will be ignored.
>
>
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>http://docs.yahoo.com/info/terms/
>
>
>
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> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject
>and
>Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to
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To UNSUBSCRIBE, just send mail to:
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from the same email address that you subscribed. Text in the Subject
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going to work. Even the best ones have a 3-9 meter inaccuarcy. If they were
always off the exact 3 meter in a straight line, that would be fine, but
what if they are off 3 meter one place, and 3 meter the opposite way in the
next place, 10 feet further down the lawn.
This seems to me to be a very basic, yet extremly hard thing to do.
Triangulation would work, but then a person needs transmitters and a
receiver unit, and all the rest of the mishmash.
I would be very interested in hearing some other viable solutions for this.
I suppose anything can be done for money, so $500 solutions are not what we
all are looking for.
Some things I have heard of are, magnetic navigation the way birds and
sharks do it & Sun polarization effects.
How does a book worm bore a perfectly straight hole through 50 books on a
shelf? How do ants dig seperate tunnels from 2 differant directions and meet
in the middle? The ants are not using spore trails in this instance because
they have not dug the tunnels yet.
How does a wood wasp find a tiny hole in the wood wall every time it flys
back, no matter the wind direction?
-Kerry
At 08:18 AM 10/24/03 -0500, you wrote:
>I'm hoping that it will be fairly accurate. It is a small yard - and
>full of bumps and dips. GPS is too expensive for me ( $40 - $50 is my
>limit ). I've also thought about using a piezo gyro, but I haven't
>explored it much though. I've also thought about scrapping the compass
>idea and do some kind of sensor that senses the edge of unmowed grass -
>but I also have patches of dirt, clover, and dead grass. So I think the
>compass would be easier.
>
>Thank you for your ideas
>
>
>
Original Message
>From: Robert Ussery [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=yKG5eXnoGWiXKbJfcQ8Dxq8Bkdxm0DFnaklyuG5_nlMLoVwIr5ShS1GO-RUZWf0dRJYGmsUZV-uoniEbzBc]uavscience@f...[/url
>Sent: Thursday, October 23, 2003 4:03 PM
>To: basicstamps@yahoogroups.com
>Subject: Re: [noparse][[/noparse]basicstamps] Compass Choice
>
>
>Bryan -
>Just how accurate does this need to be?
>I'd stay away from using a compass if you need anything better than 30
>degree precision. Try going over your yard at 1ft. or so above the
>grass, and see what kind of precision and accuracy you get with a normal
>compass. I'd say you'd frequently get variations of 10-15 degrees, and
>occasionally even greater variance. Compasses work best when they're far
>from the ground, away from man-made or other ferrous obstructions
>(houses, gas lines, cars, metal edging, sprinkler heads, etc.) Add to
>this the electromagnetic chaos you get in close proximity to a
>two-stroke motor, and I'd say you won't get anything better than 30-50
>degree precision, and terrible accuracy. The problem with running
>compasses near motors and electronics is not one of heading offset
>(i.e., it won't always be off by 10, 15, or x degrees), but rather one
>of erratic, unreliable operation. IIRC, the compasses you mentioned
>aren't cheap (>$40?), so you may be better off going with an inexpensive
>GPS unit. Many OEM units are available nowadays with 15m accuracy for
><$120. I think several (try Trimble [noparse][[/noparse]www.trimble.com] and u-blox
>[noparse][[/noparse]www.ublox.com]) even are WAAS enabled, giving you fairly consistent 3m
>accuracy. While you won't necessarily get the same heading resolution or
>update rate that you can get with a compass, the data you do get will be
>consistently more accurate and precise. The main problem I think you'll
>run into with GPS is while maneuvering in tight spots less than the
>radius of uncertainty (is that the correct term?). How big is your yard?
>One alternate approach might be to mount the compass a couple of feet
>from the mower on a pole, much like a conventional mower handle to
>escape the EMF disturbances of the motor, and to simply manually drive
>the mower around the lawn to make an electromagnetic "map" of your yard.
>Through odometry, you can determine where you are in the yard (distance
>from the starting point), and maybe even a rough heading estimate
>(although the slipperiness of grass may preclude this option). You can
>then have a table of magnetic corrections for each region or point in
>the yard. The issue you may face here is going beyond the processing and
>speed capabilities of the Stamp. I would think this would get you to at
>least 5 degrees or so of precision (and maybe even decent accuracy).
>Combined with a backup collision/accident avoidance system (bumpers,
>buried wire, ultrasonic range detection, whatever floats your
>boat) this would probably be adequate to get a decent-looking lawn. Any
>more questions? I'm full of answers! (I never said correct ones :O) !)
>
>- Robert
>
Original Message
>From: "Bryan Smith" <bsmith@w...>
>To: <basicstamps@yahoogroups.com>
>Sent: Thursday, October 23, 2003 2:06 PM
>Subject: [noparse][[/noparse]basicstamps] Compass Choice
>
>
>> For those that are using a compass with their robot, what compass are
>> you using ?
>>
>> I've looked at the Devantech CMPS03 and the Vector 2x. My goal is to
>> use the compass to guide the mower robot in a straight path. I don't
>> actually care if the direction is accurate in regards to mounting it
>> near motors - I figure the compass will be off, but if I keep the
>> robot pointed in that direction it should still be in a straight line.
>> Any thoughts are welcome.
>>
>>
>>
>>
>>
>> [noparse][[/noparse]Non-text portions of this message have been removed]
>>
>>
>> To UNSUBSCRIBE, just send mail to:
>> basicstamps-unsubscribe@yahoogroups.com
>> from the same email address that you subscribed. Text in the Subject
>> and
>Body of the message will be ignored.
>>
>>
>> Your use of Yahoo! Groups is subject to
>> http://docs.yahoo.com/info/terms/
>>
>>
>
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject
>and Body of the message will be ignored.
>
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>Your use of Yahoo! Groups is subject to
>http://docs.yahoo.com/info/terms/
>
>
>
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> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
Very respectfully, your obedient servant.
Brig. Gen. Johnston Pettigrew
Admin@M...
WWW server hosting [url=Http://mntnweb.com]Http://mntnweb.com[/url]
Kerry Barlow
p.o. box 21
kirkwood ny
13795
607-775-1575
fence. I have a dogs radio fence. The collar receiver is all potted
components, so I cannot get at the internals of the collar to install a
sensor wire to a stamp input. Making my own receiver unit was beyond my
capabilites. I read up on that some, and designing a circuit to match the
transmitter frequency, seemed like a real mess.
-kerry
At 08:42 AM 10/24/03 -0500, you wrote:
>Thanks for your input. I've already got the mower-bot to work with the
>boundry fence. I'm wanting the robot to mow in a straight line - the
>ones I've seen mow in random directions. Hence, I was hoping that I
>could use a compass for maintaining a straight course.
>
>
Original Message
>From: Bruce Bates [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=N-NSG9ebxxJQkmID2ZP_OoPrfcz5u_TrxIKCYsKo4Jg-pTWc4nvw0tJ_7vZn8PuH8QU6nmisgVGv-nSA]bvbates@u...[/url
>Sent: Friday, October 24, 2003 8:28 AM
>To: basicstamps@yahoogroups.com
>Subject: RE: [noparse][[/noparse]basicstamps] Compass Choice
>
>
>At 08:18 AM 10/24/03 -0500, Bryan Smith wrote:
>>I'm hoping that it will be fairly accurate. It is a small yard - and
>>full of bumps and dips. GPS is too expensive for me ( $40 - $50 is my
>>limit ). I've also thought about using a piezo gyro, but I haven't
>>explored it much though. I've also thought about scrapping the compass
>
>>idea and do some kind of sensor that senses the edge of unmowed grass -
>
>>but I also have patches of dirt, clover, and dead grass. So I think
>>the compass would be easier.
>>
>>Thank you for your ideas
>
>Bryan -
>
>The robotic mowers which you see for sale generally use a buried wire
>system. The mower follows the buried wire and stays inside its bounds.
>That way you
>can set the area to be mowed. This is the same type of principle used by
>
>the devices which keep a dog within an un-fenced area.
>
>Bruce Bates
>
>
>
>
>>
Original Message
>>From: Robert Ussery [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=5ivemwMcwYbU6zL3dpOzw2Tl8_erddLRJd-3cQ4tBE44H23iRUSoSxc2CXlz7heSrtKwr0MqBKLBah0]uavscience@f...[/url
>>Sent: Thursday, October 23, 2003 4:03 PM
>>To: basicstamps@yahoogroups.com
>>Subject: Re: [noparse][[/noparse]basicstamps] Compass Choice
>>
>>
>>Bryan -
>>Just how accurate does this need to be?
>>I'd stay away from using a compass if you need anything better than 30
>>degree precision. Try going over your yard at 1ft. or so above the
>>grass, and see what kind of precision and accuracy you get with a
>>normal compass. I'd say you'd frequently get variations of 10-15
>>degrees, and occasionally even greater variance. Compasses work best
>>when they're far from the ground, away from man-made or other ferrous
>>obstructions (houses, gas lines, cars, metal edging, sprinkler heads,
>>etc.) Add to this the electromagnetic chaos you get in close proximity
>>to a two-stroke motor, and I'd say you won't get anything better than
>>30-50 degree precision, and terrible accuracy. The problem with running
>
>>compasses near motors and electronics is not one of heading offset
>>(i.e., it won't always be off by 10, 15, or x degrees), but rather one
>>of erratic, unreliable operation. IIRC, the compasses you mentioned
>>aren't cheap (>$40?), so you may be better off going with an
>>inexpensive GPS unit. Many OEM units are available nowadays with 15m
>>accuracy for <$120. I think several (try Trimble [noparse][[/noparse]www.trimble.com] and
>>u-blox
>>[noparse][[/noparse]www.ublox.com]) even are WAAS enabled, giving you fairly consistent 3m
>>accuracy. While you won't necessarily get the same heading resolution
>or
>>update rate that you can get with a compass, the data you do get will
>be
>>consistently more accurate and precise. The main problem I think you'll
>>run into with GPS is while maneuvering in tight spots less than the
>>radius of uncertainty (is that the correct term?). How big is your
>yard?
>>One alternate approach might be to mount the compass a couple of feet
>>from the mower on a pole, much like a conventional mower handle to
>>escape the EMF disturbances of the motor, and to simply manually drive
>>the mower around the lawn to make an electromagnetic "map" of your
>yard.
>>Through odometry, you can determine where you are in the yard (distance
>>from the starting point), and maybe even a rough heading estimate
>>(although the slipperiness of grass may preclude this option). You can
>>then have a table of magnetic corrections for each region or point in
>>the yard. The issue you may face here is going beyond the processing
>and
>>speed capabilities of the Stamp. I would think this would get you to at
>>least 5 degrees or so of precision (and maybe even decent accuracy).
>>Combined with a backup collision/accident avoidance system (bumpers,
>>buried wire, ultrasonic range detection, whatever floats your
>>boat) this would probably be adequate to get a decent-looking lawn. Any
>>more questions? I'm full of answers! (I never said correct ones :O) !)
>>
>>- Robert
>>
Original Message
>>From: "Bryan Smith" <bsmith@w...>
>>To: <basicstamps@yahoogroups.com>
>>Sent: Thursday, October 23, 2003 2:06 PM
>>Subject: [noparse][[/noparse]basicstamps] Compass Choice
>>
>>
>> > For those that are using a compass with their robot, what compass
>> > are you using ?
>> >
>> > I've looked at the Devantech CMPS03 and the Vector 2x. My goal is
>> > to use the compass to guide the mower robot in a straight path. I
>> > don't actually care if the direction is accurate in regards to
>> > mounting it near motors - I figure the compass will be off, but if I
>
>> > keep the robot pointed in that direction it should still be in a
>> > straight line. Any thoughts are welcome.
>> >
>> >
>> >
>> >
>> >
>> > [noparse][[/noparse]Non-text portions of this message have been removed]
>> >
>> >
>> > To UNSUBSCRIBE, just send mail to:
>> > basicstamps-unsubscribe@yahoogroups.com
>> > from the same email address that you subscribed. Text in the
>> > Subject and
>>Body of the message will be ignored.
>> >
>> >
>> > Your use of Yahoo! Groups is subject to
>> > http://docs.yahoo.com/info/terms/
>> >
>> >
>>
>>
>>
>>To UNSUBSCRIBE, just send mail to:
>> basicstamps-unsubscribe@yahoogroups.com
>>from the same email address that you subscribed. Text in the Subject
>>and Body of the message will be ignored.
>>
>>
>>Your use of Yahoo! Groups is subject to
>>http://docs.yahoo.com/info/terms/
>>
>>
>>
>>To UNSUBSCRIBE, just send mail to:
>> basicstamps-unsubscribe@yahoogroups.com
>>from the same email address that you subscribed. Text in the Subject
>>and
>>Body of the message will be ignored.
>>
>>
>>Your use of Yahoo! Groups is subject to
>>http://docs.yahoo.com/info/terms/
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject
>and Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to
>http://docs.yahoo.com/info/terms/
>
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
Very respectfully, your obedient servant.
Brig. Gen. Johnston Pettigrew
Admin@M...
WWW server hosting [url=Http://mntnweb.com]Http://mntnweb.com[/url]
Kerry Barlow
p.o. box 21
kirkwood ny
13795
607-775-1575
done. When we worked on our buried fence circuit, we were not
amplifying the signal enough. In the end, we used four transistors to
get enough gain.
RoboCut can be found at: (
http://www.lls.se/~mux/micro/robocut_us.html )
I've tried attaching a Word document that has a screen print of our
pickup circuit. I don't know if the attachment will be included. I
don't know how to upload a file to the group.
Original Message
From: Kerry Barlow [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=VihlJBBeAvMiMzztmWTWMP3wz8JQ6nh3-5x6sdZkbK9Ekw6hoajdmp2VB0IUBD2zbkDBqkoF5WnVffab]admin@m...[/url
Sent: Friday, October 24, 2003 10:01 AM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] Compass Choice
bryan: I would like to know how you made the mower work with the boundry
fence. I have a dogs radio fence. The collar receiver is all potted
components, so I cannot get at the internals of the collar to install a
sensor wire to a stamp input. Making my own receiver unit was beyond my
capabilites. I read up on that some, and designing a circuit to match
the transmitter frequency, seemed like a real mess. -kerry
At 08:42 AM 10/24/03 -0500, you wrote:
>Thanks for your input. I've already got the mower-bot to work with the
>boundry fence. I'm wanting the robot to mow in a straight line - the
>ones I've seen mow in random directions. Hence, I was hoping that I
>could use a compass for maintaining a straight course.
>
>
Original Message
>From: Bruce Bates [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=JhLIiXEpZ-XB0rb6m44_bbOz4sHD0_ofAxxTjFAr59t6-4tAN1qoWFdFZQd8o9r8rodiz1OSmeBZ_1PT]bvbates@u...[/url
>Sent: Friday, October 24, 2003 8:28 AM
>To: basicstamps@yahoogroups.com
>Subject: RE: [noparse][[/noparse]basicstamps] Compass Choice
>
>
>At 08:18 AM 10/24/03 -0500, Bryan Smith wrote:
>>I'm hoping that it will be fairly accurate. It is a small yard - and
>>full of bumps and dips. GPS is too expensive for me ( $40 - $50 is my
>>limit ). I've also thought about using a piezo gyro, but I haven't
>>explored it much though. I've also thought about scrapping the
compass
>
>>idea and do some kind of sensor that senses the edge of unmowed grass
>>-
>
>>but I also have patches of dirt, clover, and dead grass. So I think
>>the compass would be easier.
>>
>>Thank you for your ideas
>
>Bryan -
>
>The robotic mowers which you see for sale generally use a buried wire
>system. The mower follows the buried wire and stays inside its bounds.
>That way you can set the area to be mowed. This is the same type of
>principle used by
>
>the devices which keep a dog within an un-fenced area.
>
>Bruce Bates
>
>
>
>
>>
Original Message
>>From: Robert Ussery [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=eexBcxLhCtTNdJz3f8-34m_aqZaIrFim4XDkHCKZrD3-jAkIImeH8vmtX1VkqhYfyOd10DnIgcO4Wi0]uavscience@f...[/url
>>Sent: Thursday, October 23, 2003 4:03 PM
>>To: basicstamps@yahoogroups.com
>>Subject: Re: [noparse][[/noparse]basicstamps] Compass Choice
>>
>>
>>Bryan -
>>Just how accurate does this need to be?
>>I'd stay away from using a compass if you need anything better than 30
>>degree precision. Try going over your yard at 1ft. or so above the
>>grass, and see what kind of precision and accuracy you get with a
>>normal compass. I'd say you'd frequently get variations of 10-15
>>degrees, and occasionally even greater variance. Compasses work best
>>when they're far from the ground, away from man-made or other ferrous
>>obstructions (houses, gas lines, cars, metal edging, sprinkler heads,
>>etc.) Add to this the electromagnetic chaos you get in close proximity
>>to a two-stroke motor, and I'd say you won't get anything better than
>>30-50 degree precision, and terrible accuracy. The problem with
running
>
>>compasses near motors and electronics is not one of heading offset
>>(i.e., it won't always be off by 10, 15, or x degrees), but rather one
>>of erratic, unreliable operation. IIRC, the compasses you mentioned
>>aren't cheap (>$40?), so you may be better off going with an
>>inexpensive GPS unit. Many OEM units are available nowadays with 15m
>>accuracy for <$120. I think several (try Trimble [noparse][[/noparse]www.trimble.com] and
>>u-blox
>>[noparse][[/noparse]www.ublox.com]) even are WAAS enabled, giving you fairly consistent
3m
>>accuracy. While you won't necessarily get the same heading resolution
>or
>>update rate that you can get with a compass, the data you do get will
>be
>>consistently more accurate and precise. The main problem I think
>>you'll run into with GPS is while maneuvering in tight spots less than
>>the radius of uncertainty (is that the correct term?). How big is your
>yard?
>>One alternate approach might be to mount the compass a couple of feet
>>from the mower on a pole, much like a conventional mower handle to
>>escape the EMF disturbances of the motor, and to simply manually drive
>>the mower around the lawn to make an electromagnetic "map" of your
>yard.
>>Through odometry, you can determine where you are in the yard
>>(distance from the starting point), and maybe even a rough heading
>>estimate (although the slipperiness of grass may preclude this
>>option). You can then have a table of magnetic corrections for each
>>region or point in the yard. The issue you may face here is going
>>beyond the processing
>and
>>speed capabilities of the Stamp. I would think this would get you to
>>at least 5 degrees or so of precision (and maybe even decent
>>accuracy). Combined with a backup collision/accident avoidance system
>>(bumpers, buried wire, ultrasonic range detection, whatever floats
>>your
>>boat) this would probably be adequate to get a decent-looking lawn.
Any
>>more questions? I'm full of answers! (I never said correct ones :O) !)
>>
>>- Robert
>>
Original Message
>>From: "Bryan Smith" <bsmith@w...>
>>To: <basicstamps@yahoogroups.com>
>>Sent: Thursday, October 23, 2003 2:06 PM
>>Subject: [noparse][[/noparse]basicstamps] Compass Choice
>>
>>
>> > For those that are using a compass with their robot, what compass
>> > are you using ?
>> >
>> > I've looked at the Devantech CMPS03 and the Vector 2x. My goal is
>> > to use the compass to guide the mower robot in a straight path. I
>> > don't actually care if the direction is accurate in regards to
>> > mounting it near motors - I figure the compass will be off, but if
I
>
>> > keep the robot pointed in that direction it should still be in a
>> > straight line. Any thoughts are welcome.
>> >
>> >
>> >
>> >
>> >
>> > [noparse][[/noparse]Non-text portions of this message have been removed]
>> >
>> >
>> > To UNSUBSCRIBE, just send mail to:
>> > basicstamps-unsubscribe@yahoogroups.com
>> > from the same email address that you subscribed. Text in the
>> > Subject and
>>Body of the message will be ignored.
>> >
>> >
>> > Your use of Yahoo! Groups is subject to
>> > http://docs.yahoo.com/info/terms/
>> >
>> >
>>
>>
>>
>>To UNSUBSCRIBE, just send mail to:
>> basicstamps-unsubscribe@yahoogroups.com
>>from the same email address that you subscribed. Text in the Subject
>>and Body of the message will be ignored.
>>
>>
>>Your use of Yahoo! Groups is subject to
>>http://docs.yahoo.com/info/terms/
>>
>>
>>
>>To UNSUBSCRIBE, just send mail to:
>> basicstamps-unsubscribe@yahoogroups.com
>>from the same email address that you subscribed. Text in the Subject
>>and
>>Body of the message will be ignored.
>>
>>
>>Your use of Yahoo! Groups is subject to
>>http://docs.yahoo.com/info/terms/
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject
>and Body of the message will be ignored.
>
>
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>
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject
>and
Body of the message will be ignored.
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>
>
>
Very respectfully, your obedient servant.
Brig. Gen. Johnston Pettigrew
Admin@M...
WWW server hosting [url=Http://mntnweb.com]Http://mntnweb.com[/url]
Kerry Barlow
p.o. box 21
kirkwood ny
13795
607-775-1575
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
from the same email address that you subscribed. Text in the Subject
and Body of the message will be ignored.
Your use of Yahoo! Groups is subject to
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[noparse][[/noparse]Non-text portions of this message have been removed]
I don
wheels on the from that pulls the body. On the back of the box, we have
two castors. A lot of times, our castors will be pointing in a
different direction when the robot starts the wheels turning. This
tends to create a drag, and forces the robot to drift towards whichever
caster is creating the drag. I don't know if the "Fifth Wheel" would do
the same or not. Its something to think about though.
Original Message
From: smartdim@a... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=cWcZBN5W3G9hmw8gbyDdnXPqh0OXawBlzfWVoOq_QFSMOrWnrJQ5hXvDumIkMtnry8vm-oASwE8rhA]smartdim@a...[/url
Sent: Friday, October 24, 2003 10:49 AM
To: basicstamps@yahoogroups.com
Subject: Re: [noparse][[/noparse]basicstamps] Compass Choice
Maybe this approach....
I don't know how you will be able to know when to turn, but to keep a
reasonable straight line the following could be implemented.
Have a "fifth wheel" off the back of the mover (or side) with two (or
more)
roller swtiches located at the attached pivot point of the fifth wheel
on the
mover. With the mover traveling straight none of the switches are
activated.
When the mover starts to drift left or right, one of the switches will
trip the
arm of the fifth wheel that is no longer at the original position as
when the
mover was straight.
Pssible a POT at the pivot point can do the same function, of course you
will
have to calibrate limits, measure acceptable hysterisis etc.
However, I don't know how you can know when you are at the end of one
pass
and know to turn ......Maybe that is where the buried wire can override
the
straight sensing system to employ a turn??????
Ken
_____________________________________________
For those that are using a compass with their robot, what compass are
you using ?
I've looked at the Devantech CMPS03 and the Vector 2x. My goal is to
use the compass to guide the mower robot in a straight path. I don't
actually care if the direction is accurate in regards to mounting it
near motors - I figure the compass will be off, but if I keep the robot
pointed in that direction it should still be in a straight line. Any
thoughts are welcome.
[noparse][[/noparse]Non-text portions of this message have been removed]
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
from the same email address that you subscribed. Text in the Subject
and Body of the message will be ignored.
Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
Original Message
From: Kerry Barlow [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=_3CFO4CSrZcqIhhXTsEQRyXP_XmOIMlv7DufWhu8onhlDiU24sh2YxWrPRpTVAersczN59Vhxto7Xg]admin@m...[/url
Sent: Friday, October 24, 2003 11:25 AM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] Compass Choice
I think a tripod affair works better in these situations. 2 drive wheels
and a caster wheel following. I had all kinds of troubles with small
robots, until I used a single ball caster on the back. I like this idea
of a follower wheel. You could always disregard the input from the
follower wheel when you make your turn, and then reinitiate the follower
sequence in the next pass. -kerry
At 11:18 AM 10/24/03 -0500, you wrote:
>Thank you for your idea. Our proto-type is a wooden box with two big
>wheels on the from that pulls the body. On the back of the box, we
>have two castors. A lot of times, our castors will be pointing in a
>different direction when the robot starts the wheels turning. This
>tends to create a drag, and forces the robot to drift towards whichever
>caster is creating the drag. I don't know if the "Fifth Wheel" would
>do the same or not. Its something to think about though.
>
>
Original Message
>From: smartdim@a... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=DU63nvUblscAw8eWp2M5BJ6IjrJ_Y1JMNIc0burtghiMjwvzTRb2WS0LOzBOEM1h0020rE6M]smartdim@a...[/url
>Sent: Friday, October 24, 2003 10:49 AM
>To: basicstamps@yahoogroups.com
>Subject: Re: [noparse][[/noparse]basicstamps] Compass Choice
>
>
>Maybe this approach....
>
>I don't know how you will be able to know when to turn, but to keep a
>reasonable straight line the following could be implemented.
>
>Have a "fifth wheel" off the back of the mover (or side) with two (or
>more)
>roller swtiches located at the attached pivot point of the fifth wheel
>on the
>mover. With the mover traveling straight none of the switches are
>activated.
>When the mover starts to drift left or right, one of the switches will
>trip the
>arm of the fifth wheel that is no longer at the original position as
>when the
>mover was straight.
>
>Pssible a POT at the pivot point can do the same function, of course
>you will have to calibrate limits, measure acceptable hysterisis etc.
>
>However, I don't know how you can know when you are at the end of one
>pass and know to turn ......Maybe that is where the buried wire can
>override the
>straight sensing system to employ a turn??????
>
>Ken
>
>_____________________________________________
>For those that are using a compass with their robot, what compass are
>you using ?
>
>I've looked at the Devantech CMPS03 and the Vector 2x. My goal is to
>use the compass to guide the mower robot in a straight path. I don't
>actually care if the direction is accurate in regards to mounting it
>near motors - I figure the compass will be off, but if I keep the robot
>pointed in that direction it should still be in a straight line. Any
>thoughts are welcome.
>
>
>[noparse][[/noparse]Non-text portions of this message have been removed]
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject
>and Body of the message will be ignored.
>
>
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>
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject
>and
Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to
>http://docs.yahoo.com/info/terms/
>
>
>
Very respectfully, your obedient servant.
Brig. Gen. Johnston Pettigrew
Admin@M...
WWW server hosting [url=Http://mntnweb.com]Http://mntnweb.com[/url]
Kerry Barlow
p.o. box 21
kirkwood ny
13795
607-775-1575
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a caster wheel following. I had all kinds of troubles with small robots,
until I used a single ball caster on the back.
I like this idea of a follower wheel. You could always disregard the input
from the follower wheel when you make your turn, and then reinitiate the
follower sequence in the next pass.
-kerry
At 11:18 AM 10/24/03 -0500, you wrote:
>Thank you for your idea. Our proto-type is a wooden box with two big
>wheels on the from that pulls the body. On the back of the box, we have
>two castors. A lot of times, our castors will be pointing in a
>different direction when the robot starts the wheels turning. This
>tends to create a drag, and forces the robot to drift towards whichever
>caster is creating the drag. I don't know if the "Fifth Wheel" would do
>the same or not. Its something to think about though.
>
>
Original Message
>From: smartdim@a... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=6-H1-7BF1Bia1oikmoaaCDOcZ1nlSlvTm_oMYn_Lc3VZm_1GtrycQeARNwUPiaRyhZMgkZ81xA]smartdim@a...[/url
>Sent: Friday, October 24, 2003 10:49 AM
>To: basicstamps@yahoogroups.com
>Subject: Re: [noparse][[/noparse]basicstamps] Compass Choice
>
>
>Maybe this approach....
>
>I don't know how you will be able to know when to turn, but to keep a
>reasonable straight line the following could be implemented.
>
>Have a "fifth wheel" off the back of the mover (or side) with two (or
>more)
>roller swtiches located at the attached pivot point of the fifth wheel
>on the
>mover. With the mover traveling straight none of the switches are
>activated.
>When the mover starts to drift left or right, one of the switches will
>trip the
>arm of the fifth wheel that is no longer at the original position as
>when the
>mover was straight.
>
>Pssible a POT at the pivot point can do the same function, of course you
>will
>have to calibrate limits, measure acceptable hysterisis etc.
>
>However, I don't know how you can know when you are at the end of one
>pass
>and know to turn ......Maybe that is where the buried wire can override
>the
>straight sensing system to employ a turn??????
>
>Ken
>
>_____________________________________________
>For those that are using a compass with their robot, what compass are
>you using ?
>
>I've looked at the Devantech CMPS03 and the Vector 2x. My goal is to
>use the compass to guide the mower robot in a straight path. I don't
>actually care if the direction is accurate in regards to mounting it
>near motors - I figure the compass will be off, but if I keep the robot
>pointed in that direction it should still be in a straight line. Any
>thoughts are welcome.
>
>
>[noparse][[/noparse]Non-text portions of this message have been removed]
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject
>and Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to
>http://docs.yahoo.com/info/terms/
>
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
Very respectfully, your obedient servant.
Brig. Gen. Johnston Pettigrew
Admin@M...
WWW server hosting [url=Http://mntnweb.com]Http://mntnweb.com[/url]
Kerry Barlow
p.o. box 21
kirkwood ny
13795
607-775-1575
have even tried the experiment of taking a electronic compass out to a lawn
and actually trying the experiment to see if it will do the trick. Do not
NECESSARILY rely on antidotal information. The compass just MAY be the
solution you are looking for. If you can afford it just do the experiment.
Mount it on a conventional power mower and see. Gather your own data and
then you can say yes or no.
My 2 cents!
Vic
________________________________________________________
Victor Fraenckel - The Windman
vfraenc1 ATSIGN nycap DOT rr DOTcom
KC2GUI
Home of the WindReader Electronic Theodolite
Read the WIND
"Victory at all costs, victory in spite of all terror, victory however long
and hard the road may be; for without victory there is no survival."
- Winston [noparse][[/noparse]Leonard Spencer] Churchill (1874 - 1965)
Dost thou not know, my son, with how little wisdom the world is governed?
-Count Oxenstierna (ca 1620) to the young King Gustavus Adolphus
Setup instructions include a compass calibration for magnetic North at
your site by turning the mower 360 degrees several times. There is very
little ferrous metal in this mower, so Vic's point is well taken.
Dennis
Original Message
From: Vic Fraenckel [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=Po-Ypll40QWjK__iptrLJak9LKe0EpDkljJ2VQVyPxIRvai-gwGdAO8lNNy-I1KbwvkYKDVPVV7LFHP3GWnm]vfraenc1@n...[/url
Sent: Friday, October 24, 2003 10:09 AM
To: BasicStamps
Subject: [noparse][[/noparse]basicstamps] RE: Compass Choice
So far in this thread I have not seen anyone's post that states that
they have even tried the experiment of taking a electronic compass out
to a lawn and actually trying the experiment to see if it will do the
trick. Do not NECESSARILY rely on antidotal information. The compass
just MAY be the solution you are looking for. If you can afford it just
do the experiment. Mount it on a conventional power mower and see.
Gather your own data and then you can say yes or no.
My 2 cents!
Vic
________________________________________________________
Victor Fraenckel - The Windman
vfraenc1 ATSIGN nycap DOT rr DOTcom
KC2GUI
Home of the WindReader Electronic Theodolite
Read the WIND
"Victory at all costs, victory in spite of all terror, victory however
long and hard the road may be; for without victory there is no
survival."
- Winston [noparse][[/noparse]Leonard Spencer] Churchill (1874 - 1965)
Dost thou not know, my son, with how little wisdom the world is
governed? -Count Oxenstierna (ca 1620) to the young King Gustavus
Adolphus
> I've tried attaching a Word document that has a screen print of our
> pickup circuit. I don't know if the attachment will be included. I
> don't know how to upload a file to the group.
Attachments are not allowed to prevent virus propagation.
To share files with the members of the forum you need to upload them at:
http://groups.yahoo.com/group/basicstamps/files/
(you need to Sign in using your Yahoo ID and password)
Saludos,
Aristides Alvarez
International Education Program Developer
aalvarez@p...
Parallax, Inc. www.parallax.com
Rocklin, California
USA
Original Message
From: Vic Fraenckel [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=GfvFSgXm8iMxEJnqxpcSZqsODdZZ8QrZISru4U6G5wuow_am1DQSP7BNaWKZkK2wy-sFE9vtbMypqpT-t5s]vfraenc1@n...[/url
Sent: Friday, October 24, 2003 12:09 PM
To: BasicStamps
Subject: [noparse][[/noparse]basicstamps] RE: Compass Choice
So far in this thread I have not seen anyone's post that states that
they have even tried the experiment of taking a electronic compass out
to a lawn and actually trying the experiment to see if it will do the
trick. Do not NECESSARILY rely on antidotal information. The compass
just MAY be the solution you are looking for. If you can afford it just
do the experiment. Mount it on a conventional power mower and see.
Gather your own data and then you can say yes or no.
My 2 cents!
Vic
________________________________________________________
Victor Fraenckel - The Windman
vfraenc1 ATSIGN nycap DOT rr DOTcom
KC2GUI
Home of the WindReader Electronic Theodolite
Read the WIND
"Victory at all costs, victory in spite of all terror, victory however
long and hard the road may be; for without victory there is no
survival."
- Winston [noparse][[/noparse]Leonard Spencer] Churchill (1874 - 1965)
Dost thou not know, my son, with how little wisdom the world is
governed? -Count Oxenstierna (ca 1620) to the young King Gustavus
Adolphus
To UNSUBSCRIBE, just send mail to:
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Original Message
From: Aristides Alvarez [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=cz3aWvGwOS8V6ZRAIM3TCOdGV4LPu8PC8hZohq0MDjSwdMFqKCBBFhU6cr2ecvhB1_nVdsZG7yeh2p2thIA]aalvarez@p...[/url
Sent: Friday, October 24, 2003 12:38 PM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] Compass Choice
Hello Bryan.
> I've tried attaching a Word document that has a screen print of our
> pickup circuit. I don't know if the attachment will be included. I
> don't know how to upload a file to the group.
Attachments are not allowed to prevent virus propagation.
To share files with the members of the forum you need to upload them at:
http://groups.yahoo.com/group/basicstamps/files/
(you need to Sign in using your Yahoo ID and password)
Saludos,
Aristides Alvarez
International Education Program Developer
aalvarez@p...
Parallax, Inc. www.parallax.com
Rocklin, California
USA
To UNSUBSCRIBE, just send mail to:
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do agree with you. I was actually approaching the problem from the point of
view of a commercial product. I don't think a compass can be relied upon to
work in any given yard, although it may work very well indeed in your
particular location. A lot of it is also dependent on your particular
design. I think that as long as you isolate the compass sufficiently from
the metal of the mower and the engine, it will be accurate enough to give
you a decent lawn-mowing, while it may not be suitable for a commercial
product. Bottom line, don't take me too seriously... I don't know
everything, and I don't pretend to. I was just expressing my initial
impression.
- Robert
Original Message
From: "Vic Fraenckel" <vfraenc1@n...>
To: "BasicStamps" <basicstamps@yahoogroups.com>
Sent: Friday, October 24, 2003 11:08 AM
Subject: [noparse][[/noparse]basicstamps] RE: Compass Choice
> So far in this thread I have not seen anyone's post that states that they
> have even tried the experiment of taking a electronic compass out to a
lawn
> and actually trying the experiment to see if it will do the trick. Do not
> NECESSARILY rely on antidotal information. The compass just MAY be the
> solution you are looking for. If you can afford it just do the experiment.
> Mount it on a conventional power mower and see. Gather your own data and
> then you can say yes or no.
>
> My 2 cents!
>
> Vic
> ________________________________________________________
>
> Victor Fraenckel - The Windman
> vfraenc1 ATSIGN nycap DOT rr DOTcom
> KC2GUI
>
> Home of the WindReader Electronic Theodolite
> Read the WIND
>
> "Victory at all costs, victory in spite of all terror, victory however
long
> and hard the road may be; for without victory there is no survival."
> - Winston [noparse][[/noparse]Leonard Spencer] Churchill (1874 - 1965)
>
> Dost thou not know, my son, with how little wisdom the world is governed?
> -Count Oxenstierna (ca 1620) to the young King Gustavus Adolphus
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
dragging my feet as to what I should buy. I'm trying to decide between
the Devantech CMPS03, Vector 2x, or maybe the Dinsmore 1525. I've been
leaning towards the Devantech CMPS03.
Original Message
From: Robert Ussery [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=0EKRnq3VP5VjWmbOyabHPJNdZHNzvsBDtqkYjE-T66Qhb5MWy13OWXx-2v0w4qHKZVsGikdKA7L_SEJs]uavscience@f...[/url
Sent: Friday, October 24, 2003 3:29 PM
To: basicstamps@yahoogroups.com
Subject: Re: [noparse][[/noparse]basicstamps] RE: Compass Choice
Despite the pessimistic opinions expressed in my previous post, I
actually do agree with you. I was actually approaching the problem from
the point of view of a commercial product. I don't think a compass can
be relied upon to work in any given yard, although it may work very well
indeed in your particular location. A lot of it is also dependent on
your particular design. I think that as long as you isolate the compass
sufficiently from the metal of the mower and the engine, it will be
accurate enough to give you a decent lawn-mowing, while it may not be
suitable for a commercial product. Bottom line, don't take me too
seriously... I don't know everything, and I don't pretend to. I was just
expressing my initial impression.
- Robert
Original Message
From: "Vic Fraenckel" <vfraenc1@n...>
To: "BasicStamps" <basicstamps@yahoogroups.com>
Sent: Friday, October 24, 2003 11:08 AM
Subject: [noparse][[/noparse]basicstamps] RE: Compass Choice
> So far in this thread I have not seen anyone's post that states that
> they have even tried the experiment of taking a electronic compass out
> to a
lawn
> and actually trying the experiment to see if it will do the trick. Do
> not NECESSARILY rely on antidotal information. The compass just MAY be
> the solution you are looking for. If you can afford it just do the
> experiment. Mount it on a conventional power mower and see. Gather
> your own data and then you can say yes or no.
>
> My 2 cents!
>
> Vic
> ________________________________________________________
>
> Victor Fraenckel - The Windman
> vfraenc1 ATSIGN nycap DOT rr DOTcom
> KC2GUI
>
> Home of the WindReader Electronic Theodolite
> Read the WIND
>
> "Victory at all costs, victory in spite of all terror, victory however
long
> and hard the road may be; for without victory there is no survival."
> - Winston [noparse][[/noparse]Leonard Spencer] Churchill (1874 - 1965)
>
> Dost thou not know, my son, with how little wisdom the world is
> governed? -Count Oxenstierna (ca 1620) to the young King Gustavus
> Adolphus
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject
> and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
>
>
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bsmith@w... writes:
We have been following RoboCut. He gives schematics of the work he has
done. When we worked on our buried fence circuit, we were not
amplifying the signal enough. In the end, we used four transistors to
get enough gain.
RoboCut can be found at: (
http://www.lls.se/~mux/micro/robocut_us.html )
I've tried attaching a Word document that has a screen print of our
pickup circuit. I don't know if the attachment will be included. I
don't know how to upload a file to the group.
Brian,
What did you decide to do on the compass choice? Did you have a chance to
upload the file to the user group?
This was an interesting thread.
Tim
[noparse][[/noparse]Non-text portions of this message have been removed]
something like "We have been folowing Robocut". When we first started
out, we were uning a 741. It would only pick up within a few inches.
The new circuit goes around 4 feet. This circuit has four transistors (
2N4401 ) The coil is not shown on the circuit. There is a voltage
source ( looks like a squigly with a circle around it on the left hand
side ). On the real circuit, we us a ( TV 1363 - B ). We had to play
around with the capacitors. The capacitors off the emmiter side are
Electrolitic @ 1uF. The other capacitors are Ceramic. The capacitor
values were done by guessing. We originally had the electrolitic and
ceramic capacitors switched. We used an oscilloscope to play around
with the different values for the capacitors.
I will send the results to the group as to how things worked out. I'm
probably going to buy the Devantech CMPS03 - but not until Christmas
day.
Original Message
From: Trkeenan@a... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=3WpwJfIZZECVz_rICG88oGOwaKSa4qq5IgnROdszxYHnzoStgnxXUUFjalMTawIeJCF9psVo]Trkeenan@a...[/url
Sent: Sunday, October 26, 2003 9:45 PM
To: basicstamps@yahoogroups.com
Subject: Re: [noparse][[/noparse]basicstamps] Compass Choice
In a message dated 10/24/2003 9:45:31 AM Mountain Standard Time,
bsmith@w... writes:
We have been following RoboCut. He gives schematics of the work he has
done. When we worked on our buried fence circuit, we were not
amplifying the signal enough. In the end, we used four transistors to
get enough gain.
RoboCut can be found at: ( http://www.lls.se/~mux/micro/robocut_us.html
)
I've tried attaching a Word document that has a screen print of our
pickup circuit. I don't know if the attachment will be included. I
don't know how to upload a file to the group. Brian,
What did you decide to do on the compass choice? Did you have a chance
to
upload the file to the user group?
This was an interesting thread.
Tim
[noparse][[/noparse]Non-text portions of this message have been removed]
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
from the same email address that you subscribed. Text in the Subject
and Body of the message will be ignored.
Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
Thanks for your circuit.
The TV 1363 - B coil, what type is it? Who is the manufacturer?
What is the frequency that is broadcast by the fence?
Harry
Stamp Robotics to the next level
www.bluebelldesign.com
--- In basicstamps@yahoogroups.com, "Bryan Smith" <bsmith@w...> wrote:
> Everyone was very helpful. I uploaded the Word document - Its
called
> something like "We have been folowing Robocut". When we first
started
> out, we were uning a 741. It would only pick up within a few
inches.
> The new circuit goes around 4 feet. This circuit has four
transistors (
> 2N4401 ) The coil is not shown on the circuit. There is a voltage
> source ( looks like a squigly with a circle around it on the left
hand
> side ). On the real circuit, we us a ( TV 1363 - B ). We had to
play
> around with the capacitors. The capacitors off the emmiter side are
> Electrolitic @ 1uF. The other capacitors are Ceramic. The
capacitor
> values were done by guessing. We originally had the electrolitic
and
> ceramic capacitors switched. We used an oscilloscope to play around
> with the different values for the capacitors.
>
> I will send the results to the group as to how things worked out.
I'm
> probably going to buy the Devantech CMPS03 - but not until Christmas
> day.
>
>
>
Original Message
> From: Trkeenan@a... [noparse][[/noparse]mailto:Trkeenan@a...]
> Sent: Sunday, October 26, 2003 9:45 PM
> To: basicstamps@yahoogroups.com
> Subject: Re: [noparse][[/noparse]basicstamps] Compass Choice
>
>
> In a message dated 10/24/2003 9:45:31 AM Mountain Standard Time,
> bsmith@w... writes:
> We have been following RoboCut. He gives schematics of the work he
has
> done. When we worked on our buried fence circuit, we were not
> amplifying the signal enough. In the end, we used four transistors
to
> get enough gain.
>
> RoboCut can be found at: (
http://www.lls.se/~mux/micro/robocut_us.html
> )
>
> I've tried attaching a Word document that has a screen print of our
> pickup circuit. I don't know if the attachment will be included. I
> don't know how to upload a file to the group. Brian,
>
> What did you decide to do on the compass choice? Did you have a
chance
> to
> upload the file to the user group?
>
> This was an interesting thread.
>
> Tim
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the
Subject
> and Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
it. Our frequency is 68000.
I imagine the capacitor and coil values can be tweaked to match whatever
frequency you want to use.
The robocut web site has a formula about the capacitor and coil. I
think his ROT is our Square Root.
Sorry I can't be much more help. We are computer programmers and have
picked up on things and tried
Other things - we guess a lot, and most of the time we can't explain why
it works a certain way.
Original Message
From: harrywlewis [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=eEqxnm-kxNLoSt4iBeFQouRGk8o5VmobOepGZBSCsHTZKmlNq0etjQ_UPbx9HgeYkR-FtQZbl9_4rLUWvzJEODQ]harry_w_lewis@h...[/url
Sent: Monday, October 27, 2003 4:18 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Re: Compass Choice
Hi Bryan,
Thanks for your circuit.
The TV 1363 - B coil, what type is it? Who is the manufacturer?
What is the frequency that is broadcast by the fence?
Harry
Stamp Robotics to the next level
www.bluebelldesign.com
--- In basicstamps@yahoogroups.com, "Bryan Smith" <bsmith@w...> wrote:
> Everyone was very helpful. I uploaded the Word document - Its
called
> something like "We have been folowing Robocut". When we first
started
> out, we were uning a 741. It would only pick up within a few
inches.
> The new circuit goes around 4 feet. This circuit has four
transistors (
> 2N4401 ) The coil is not shown on the circuit. There is a voltage
> source ( looks like a squigly with a circle around it on the left
hand
> side ). On the real circuit, we us a ( TV 1363 - B ). We had to
play
> around with the capacitors. The capacitors off the emmiter side are
> Electrolitic @ 1uF. The other capacitors are Ceramic. The
capacitor
> values were done by guessing. We originally had the electrolitic
and
> ceramic capacitors switched. We used an oscilloscope to play around
> with the different values for the capacitors.
>
> I will send the results to the group as to how things worked out.
I'm
> probably going to buy the Devantech CMPS03 - but not until Christmas
> day.
>
>
>
Original Message
> From: Trkeenan@a... [noparse][[/noparse]mailto:Trkeenan@a...]
> Sent: Sunday, October 26, 2003 9:45 PM
> To: basicstamps@yahoogroups.com
> Subject: Re: [noparse][[/noparse]basicstamps] Compass Choice
>
>
> In a message dated 10/24/2003 9:45:31 AM Mountain Standard Time,
> bsmith@w... writes:
> We have been following RoboCut. He gives schematics of the work he
has
> done. When we worked on our buried fence circuit, we were not
> amplifying the signal enough. In the end, we used four transistors
to
> get enough gain.
>
> RoboCut can be found at: (
http://www.lls.se/~mux/micro/robocut_us.html
> )
>
> I've tried attaching a Word document that has a screen print of our
> pickup circuit. I don't know if the attachment will be included. I
> don't know how to upload a file to the group. Brian,
>
> What did you decide to do on the compass choice? Did you have a
chance
> to
> upload the file to the user group?
>
> This was an interesting thread.
>
> Tim
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
>
>
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