From chchrobotics@lists.linuxnut.co.nz Mon Mar 5 06:27:48 2007
From: chchrobotics@lists.linuxnut.co.nz (Bry Ashman)
Date: Mon, 5 Mar 2007 19:27:48 +1300
Subject: [chbot] Beer Lauching Fridge
Message-ID: <27feac3e0703042227o108665e4y4b1e53a8361aa216@mail.gmail.com>
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Just something interesting I stumbled across :)
Info: http://www.duke.edu/~jwc13/beerlauncher.html
Video:
http://www.metacafe.com/watch/445498/robotic_beer_launching_refrigerator/
Bry
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Just something interesting I stumbled across :)
Info: http://www.duke.edu/~jwc13/beerlauncher.html
Video:
http://www.metacafe.com/watch/445498/robotic_beer_launching_refrigerator/
Bry
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From chchrobotics@lists.linuxnut.co.nz Mon Mar 5 09:31:04 2007
From: chchrobotics@lists.linuxnut.co.nz (Vilna Gough-Jones)
Date: Mon, 05 Mar 2007 22:31:04 +1300
Subject: [chbot] Beer Lauching Fridge
In-Reply-To: <27feac3e0703042227o108665e4y4b1e53a8361aa216@mail.gmail.com>
Message-ID: <0JEF006ZRBRYV110@smtp4.clear.net.nz>
This is a multi-part message in MIME format.
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charset="windows-1250"
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Thanks Bry=85 this is a great way to introduce the potential of robotics =
to my
year 13 students.
Cheers, Vilna
=20
_____ =20
From: chchrobotics-admin@lists.linuxnut.co.nz
[mailto:chchrobotics-admin@lists.linuxnut.co.nz] On Behalf Of Bry Ashman
Sent: Monday, 5 March 2007 7:28 p.m.
To: chchrobotics@lists.linuxnut.co.nz
Subject: [chbot] Beer Lauching Fridge
=20
Just something interesting I stumbled across :)
Info: HYPERLINK
"http://www.duke.edu/~jwc13/beerlauncher.html"http://www.duke.edu/~jwc13/=
bee
rlauncher.html
Video: HYPERLINK
"http://www.metacafe.com/watch/445498/robotic_beer_launching_refrigerator=
/"h
ttp://www.metacafe.com/watch/445498/robotic_beer_launching_refrigerator/
Bry
--
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.5.446 / Virus Database: 268.18.7/710 - Release Date: =
4/03/2007
1:58 p.m.
--=20
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.5.446 / Virus Database: 268.18.7/710 - Release Date: =
4/03/2007
1:58 p.m.
=20
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charset="windows-1250"
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Thanks Bry… this is a great =
way to
introduce the potential of robotics to my year 13 =
students.
Cheers, =
Vilna
From:
chchrobotics-admin@lists.linuxnut.co.nz
[mailto:chchrobotics-admin@lists.linuxnut.co.nz] On Behalf Of Bry Ashman
Sent: Monday, 5 March =
2007 7:28
p.m.
To: =
chchrobotics@lists.linuxnut.co.nz
Subject: [chbot]
Beer Lauching Fridge
Just something
interesting I stumbled across :)
Info: http://www.duke.edu=
/~jwc13/beerlauncher.html
Video: http://www.metacafe.com/watch/445498/robotic_beer_launching_ref=
rigerator/
Bry
--
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.5.446 / Virus Database: 268.18.7/710 - Release Date: =
4/03/2007 1:58
p.m.
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.5.446 / Virus Database: 268.18.7/710 - Release Date: =
4/03/2007 1:58 p.m.
------=_NextPart_000_0028_01C75F75.F6DC17E0--
From chchrobotics@lists.linuxnut.co.nz Mon Mar 5 10:59:00 2007
From: chchrobotics@lists.linuxnut.co.nz (Bry Ashman)
Date: Mon, 5 Mar 2007 23:59:00 +1300
Subject: [chbot] Beer Lauching Fridge
In-Reply-To: <0JEF006ZRBRYV110@smtp4.clear.net.nz>
References: <27feac3e0703042227o108665e4y4b1e53a8361aa216@mail.gmail.com>
<0JEF006ZRBRYV110@smtp4.clear.net.nz>
Message-ID: <27feac3e0703050259u25112aabobef02521afecdad9@mail.gmail.com>
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lol, just realised in my hurry I left the 'n' out of launching. It is
certainly a project with a huge cool factor, and not over the moon complex
as far as you don't really have to take and process any input from the
environment. =)
Bry
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lol, just realised in my hurry I left the 'n' out of launching. It is certainly a project with a huge cool factor, and not over the moon complex as far as you don't really have to take and process any input from the environment. =)
Bry
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From chchrobotics@lists.linuxnut.co.nz Mon Mar 5 20:21:27 2007
From: chchrobotics@lists.linuxnut.co.nz (Andrew Errington)
Date: Tue, 06 Mar 2007 09:21:27 +1300
Subject: [chbot] For Peter
Message-ID: <0JEG002ZU5VSPM30@smtp5.clear.net.nz>
At the last meeting we were talking about steam powered robots. What
should appear on the internet shortly afterwards?
http://www.boingboing.net/2007/02/23/steampunk_walking_ro.html
=;^)
A
From chchrobotics@lists.linuxnut.co.nz Mon Mar 5 20:26:06 2007
From: chchrobotics@lists.linuxnut.co.nz (John Tiler)
Date: Mon, 05 Mar 2007 20:26:06 +0000
Subject: [chbot] Beer Lauching Fridge
In-Reply-To: <27feac3e0703050259u25112aabobef02521afecdad9@mail.gmail.com>
Message-ID:
I dont think you'd be able to catch them after a couple of beers tho....
lol, awesome idea and a great piece of engineering!
>From: "Bry Ashman"
>Reply-To: chchrobotics@lists.linuxnut.co.nz
>To: chchrobotics@lists.linuxnut.co.nz
>Subject: Re: [chbot] Beer Lauching Fridge
>Date: Mon, 5 Mar 2007 23:59:00 +1300
>
>lol, just realised in my hurry I left the 'n' out of launching. It is
>certainly a project with a huge cool factor, and not over the moon complex
>as far as you don't really have to take and process any input from the
>environment. =)
>
>Bry
_________________________________________________________________
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From chchrobotics@lists.linuxnut.co.nz Tue Mar 6 07:28:22 2007
From: chchrobotics@lists.linuxnut.co.nz (Pete Morris)
Date: Tue, 06 Mar 2007 20:28:22 +1300
Subject: [chbot] For Peter
References: <0JEG002ZU5VSPM30@smtp5.clear.net.nz>
Message-ID: <003801c75fc1$05c45bf0$bd00a8c0@blue>
that's so cool ! Thanks for posting it here.
Not much in the way of maze-solving ability, but a real work of art...
Pete
----- Original Message -----
From: "Andrew Errington"
To:
Sent: Tuesday, March 06, 2007 9:21 AM
Subject: [chbot] For Peter
> At the last meeting we were talking about steam powered robots. What
> should appear on the internet shortly afterwards?
>
> http://www.boingboing.net/2007/02/23/steampunk_walking_ro.html
>
> =;^)
>
> A
>
> _______________________________________________
> Chchrobotics mailing list
> Chchrobotics@lists.linuxnut.co.nz
> http://lists.ourshack.com/mailman/listinfo/chchrobotics
From chchrobotics@lists.linuxnut.co.nz Wed Mar 7 08:35:21 2007
From: chchrobotics@lists.linuxnut.co.nz (Carl Ranson)
Date: Wed, 07 Mar 2007 21:35:21 +1300
Subject: [chbot] Have I killed my bot battery?
Message-ID: <45EE7949.9030708@paradise.net.nz>
So I left my bot's electronics running on the bench overnight and my
battery is down to 7 volts (its a 12v SLA)
I've just put it on the charger and nothing happened.
The charger I have is a jaycar one (http://tinyurl.com/ytlhkx) and I
note that many of the chargers on their website have a note "These
chargers will not charge a totally flat battery".
Is it possible that 7v is low enough to make the battery non-detectable
to the charger? Is there any way to trick the charger into detecting it?
thanks team.
C
From chchrobotics@lists.linuxnut.co.nz Wed Mar 7 09:17:08 2007
From: chchrobotics@lists.linuxnut.co.nz (John Tiler)
Date: Wed, 07 Mar 2007 09:17:08 +0000
Subject: [chbot] Have I killed my bot battery?
In-Reply-To: <45EE7949.9030708@paradise.net.nz>
Message-ID:
perhaps. If its a 12V sla try a car battery charger on it, if you do....
Pump it up a bit and then try using ur charger.
>From: Carl Ranson
>Reply-To: chchrobotics@lists.linuxnut.co.nz
>To: chbot
>Subject: [chbot] Have I killed my bot battery?
>Date: Wed, 07 Mar 2007 21:35:21 +1300
>
>So I left my bot's electronics running on the bench overnight and my
>battery is down to 7 volts (its a 12v SLA)
>
>I've just put it on the charger and nothing happened.
>
>The charger I have is a jaycar one (http://tinyurl.com/ytlhkx) and I
>note that many of the chargers on their website have a note "These
>chargers will not charge a totally flat battery".
>
>Is it possible that 7v is low enough to make the battery non-detectable
>to the charger? Is there any way to trick the charger into detecting it?
>
>thanks team.
>C
>
>
>
>
>_______________________________________________
>Chchrobotics mailing list
>Chchrobotics@lists.linuxnut.co.nz
>http://lists.ourshack.com/mailman/listinfo/chchrobotics
_________________________________________________________________
With tax season right around the corner, make sure to follow these few
simple tips.
http://articles.moneycentral.msn.com/Taxes/PreparationTips/PreparationTips.aspx?icid=HMFebtagline
From chchrobotics@lists.linuxnut.co.nz Wed Mar 7 10:49:55 2007
From: chchrobotics@lists.linuxnut.co.nz (Carl Ranson)
Date: Wed, 07 Mar 2007 23:49:55 +1300
Subject: [chbot] Micromouse Simulator
In-Reply-To: <453679de.1d6.3881.739753052@ihug.co.nz>
References: <453679de.1d6.3881.739753052@ihug.co.nz>
Message-ID: <45EE98D3.7080002@paradise.net.nz>
Finally looked into this.
The thing that threw me when i first looked was the maze.c program. I
thought it was supposed to be the "simulated mouse" code but it just
seems to be some tool for converting the maze file formats.
The solver program is good, but doesn't really teach us much. What I
really want is a tool that will let you run your own solver algorithm
too see how well it solves the maze.
Is there anything like this available yet?
C
What does the
rjtp@ihug.co.nz wrote:
>Attached is the micromouse simulator that I promised to send
>at last nights meeting.
>This project was started & dropped in 1997, never the less
>it is still a work in progress!
>The zip file contains a selection of mazes from microcomouse
>championships and a program cmouse.exe.
>The program runs under DOS and can display, edit and solve
>mazes.
>Unzip the mmouse.zip into a folder of your choice.
>Run the program by typing cmouse at the command line or by
>double clicking cmouse.exe from explorer.
>When the program starts press F4 then F10 to select a maze
>and have a simulated mouse chase around the maze to solve
>it.
>Use your mouse left and right buttons to edit the maze.
>I think the solver has a small bug. See if you can spot it.
>Feel free to send me new championship mazes and suggestions.
>It is a real credit to Microsoft(TM) that this program runs
>unchanged after so many generations of OS.
>I expect to have a Python version running under Windows,
>Linux and OSX for new mouse software testing.
>
>Richard Jones
>19 October 2006
>rjtp@ihug.co.nz
>
>
From chchrobotics@lists.linuxnut.co.nz Wed Mar 7 10:54:51 2007
From: chchrobotics@lists.linuxnut.co.nz (Carl Ranson)
Date: Wed, 07 Mar 2007 23:54:51 +1300
Subject: [chbot] Have I killed my bot battery?
In-Reply-To:
References:
Message-ID: <45EE99FB.1090109@paradise.net.nz>
Seems I was correct.
I managed to kick start it by putting a couple of charged nicad's in
serially to raise the voltage. The charger is slow enough to change
state that i was able to connect the battery up before it shut down again.
Probably an idiotic way of doing it but it now seems to be charging so
I'm happy.
Off to research low voltage cutout circuits so I don't get this again.
C
John Tiler wrote:
> perhaps. If its a 12V sla try a car battery charger on it, if you do....
> Pump it up a bit and then try using ur charger.
>
>
>
>
>> From: Carl Ranson
>> Reply-To: chchrobotics@lists.linuxnut.co.nz
>> To: chbot
>> Subject: [chbot] Have I killed my bot battery?
>> Date: Wed, 07 Mar 2007 21:35:21 +1300
>>
>> So I left my bot's electronics running on the bench overnight and my
>> battery is down to 7 volts (its a 12v SLA)
>>
>> I've just put it on the charger and nothing happened.
>>
>> The charger I have is a jaycar one (http://tinyurl.com/ytlhkx) and I
>> note that many of the chargers on their website have a note "These
>> chargers will not charge a totally flat battery".
>>
>> Is it possible that 7v is low enough to make the battery non-detectable
>> to the charger? Is there any way to trick the charger into detecting it?
>>
>> thanks team.
>> C
>>
>>
>>
>>
>> _______________________________________________
>> Chchrobotics mailing list
>> Chchrobotics@lists.linuxnut.co.nz
>> http://lists.ourshack.com/mailman/listinfo/chchrobotics
>
>
> _________________________________________________________________
> With tax season right around the corner, make sure to follow these few
> simple tips.
> http://articles.moneycentral.msn.com/Taxes/PreparationTips/PreparationTips.aspx?icid=HMFebtagline
>
>
>
> _______________________________________________
> Chchrobotics mailing list
> Chchrobotics@lists.linuxnut.co.nz
> http://lists.ourshack.com/mailman/listinfo/chchrobotics
>
From chchrobotics@lists.linuxnut.co.nz Wed Mar 7 11:12:56 2007
From: chchrobotics@lists.linuxnut.co.nz (Carl Ranson)
Date: Thu, 08 Mar 2007 00:12:56 +1300
Subject: [chbot] Micromouse maze solving strategies
Message-ID: <45EE9E38.7010200@paradise.net.nz>
I've been thinking this problem through and I can see that finding the
shortest/fastest path is equivalent to the shortest path problem in
graph theory.
Now Im thinking about the process of discovery, an whether you'd need to
investigate the whole maze or not. The obvious process to discover the
maze is to always go straight, right, left or back as possible and
backtrack to spots where there were more than one possibility. This is
gaurenteed to discover the whole maze and seems to be what the simulator
program does.
If the goal always is always in the center of the maze, would it be
possible to gear the turn decisions with the goal of discovering the
area between the center of the maze and start point first?
C
From chchrobotics@lists.linuxnut.co.nz Wed Mar 7 19:52:13 2007
From: chchrobotics@lists.linuxnut.co.nz (Richard Jones)
Date: Thu, 08 Mar 2007 08:52:13 +1300
Subject: [chbot] Micromouse maze solving strategies and maze construction.
Message-ID: <45ef17ed.3ad.2774.336257720@ihug.co.nz>
Here's my take on competition maze solving.
Given that the solution is unknown it may not be possible to
fully optimise search strategies, it is the luck of the draw
for a given maze. A really dumb solver might stumble into
the solution quicker than a smart algorithm for some mazes,
but probably much less often. Given that, including mouse
dynamics in the choice of which paths to search first and
not searching areas that can't be part of the solution seem
sensible to minimise the search time.
I have an intention to do something with Python and SWIG to
replace my old solver with something that is more up to date
for working under Linux and Windows GUIs. (Any other
sugestions would be most welcome). I should be able to dig
out all the code for the old simulator and email it to
anyone who wants to read it. I think the solver itself is
only a few lines of 'C'. There is an assumption that the
maze has no walls, as the mouse starts to explore it adds
the discovered walls in to the image of the maze and
re-solves to decide where to go next.
Now that holidays are over and family have all left I will
have more time for robotics, once I've got MythTv working
with my new satellite receiver ;-)
I have built two maze sections 6 x 6 cells and one 3 x 3
cells. I have a box full of walls but have not counted them
recently. Most of my maze walls include one end post (some
have none or two included in the length). This is probably
enough for debugging and demonstating mice, but if we want
to run a competition we need to design and build a full size
maze or buy one.
This is the best source of micromouse ideas that I have
found: http://micromouse.cannock.ac.uk/
Cheers
Richard
> I've been thinking this problem through and I can see that
> finding the shortest/fastest path is equivalent to the
> shortest path problem in graph theory.
>
> Now Im thinking about the process of discovery, an whether
> you'd need to investigate the whole maze or not. The
> obvious process to discover the maze is to always go
> straight, right, left or back as possible and backtrack
> to spots where there were more than one possibility. This
> is gaurenteed to discover the whole maze and seems to be
> what the simulator program does.
>
> If the goal always is always in the center of the maze,
> would it be possible to gear the turn decisions with the
> goal of discovering the area between the center of the
> maze and start point first? C
>
> _______________________________________________
> Chchrobotics mailing list
> Chchrobotics@lists.linuxnut.co.nz
> http://lists.ourshack.com/mailman/listinfo/chchrobotics
>
From chchrobotics@lists.linuxnut.co.nz Wed Mar 7 23:44:29 2007
From: chchrobotics@lists.linuxnut.co.nz (Andrew Errington)
Date: Thu, 08 Mar 2007 12:44:29 +1300
Subject: [chbot] Have I killed my bot battery?
In-Reply-To: <45EE99FB.1090109@paradise.net.nz>
References:
<45EE99FB.1090109@paradise.net.nz>
Message-ID: <0JEK005W34M6JP00@smtp3.clear.net.nz>
Here's a discussion on testing and evaluating SLA batteries:
http://www.fieldlines.com/story/2003/8/24/20535/6203
I have just bought a D3800 PSU from Dickies (on special at about $190 if
you have a Trade Card). I am now trying to charge my four SLA's as
described in the article because I am sure one of them is dud, and the
others aren't much better.
Anyway, I hope you can resurrect yours and get some more use out of it. I
have read that once they have been significantly discharged (less than
10.5V) then they are sad and won't last much longer.
Andrew
On Wed, 07 Mar 2007 23:54, you wrote:
> Seems I was correct.
> I managed to kick start it by putting a couple of charged nicad's in
> serially to raise the voltage. The charger is slow enough to change
> state that i was able to connect the battery up before it shut down
> again.
>
> Probably an idiotic way of doing it but it now seems to be charging so
> I'm happy.
>
> Off to research low voltage cutout circuits so I don't get this again.
> C
>
> John Tiler wrote:
> > perhaps. If its a 12V sla try a car battery charger on it, if you
> > do.... Pump it up a bit and then try using ur charger.
> >
> >> From: Carl Ranson
> >> Reply-To: chchrobotics@lists.linuxnut.co.nz
> >> To: chbot
> >> Subject: [chbot] Have I killed my bot battery?
> >> Date: Wed, 07 Mar 2007 21:35:21 +1300
> >>
> >> So I left my bot's electronics running on the bench overnight and my
> >> battery is down to 7 volts (its a 12v SLA)
> >>
> >> I've just put it on the charger and nothing happened.
> >>
> >> The charger I have is a jaycar one (http://tinyurl.com/ytlhkx) and I
> >> note that many of the chargers on their website have a note "These
> >> chargers will not charge a totally flat battery".
> >>
> >> Is it possible that 7v is low enough to make the battery
> >> non-detectable to the charger? Is there any way to trick the charger
> >> into detecting it?
> >>
> >> thanks team.
> >> C
> >>
> >>
> >>
> >>
> >> _______________________________________________
> >> Chchrobotics mailing list
> >> Chchrobotics@lists.linuxnut.co.nz
> >> http://lists.ourshack.com/mailman/listinfo/chchrobotics
> >
> > _________________________________________________________________
> > With tax season right around the corner, make sure to follow these few
> > simple tips.
> > http://articles.moneycentral.msn.com/Taxes/PreparationTips/PreparationT
> >ips.aspx?icid=HMFebtagline
> >
> >
> >
> > _______________________________________________
> > Chchrobotics mailing list
> > Chchrobotics@lists.linuxnut.co.nz
> > http://lists.ourshack.com/mailman/listinfo/chchrobotics
>
> _______________________________________________
> Chchrobotics mailing list
> Chchrobotics@lists.linuxnut.co.nz
> http://lists.ourshack.com/mailman/listinfo/chchrobotics
From chchrobotics@lists.linuxnut.co.nz Wed Mar 7 23:46:54 2007
From: chchrobotics@lists.linuxnut.co.nz (Andrew Errington)
Date: Thu, 08 Mar 2007 12:46:54 +1300
Subject: [chbot] Micromouse maze solving strategies and maze construction.
In-Reply-To: <45ef17ed.3ad.2774.336257720@ihug.co.nz>
References: <45ef17ed.3ad.2774.336257720@ihug.co.nz>
Message-ID: <0JEK0096O4Q7UV00@smtp5.clear.net.nz>
On Thu, 08 Mar 2007 08:52, you wrote:
> I have an intention to do something with Python and SWIG to
> replace my old solver with something that is more up to date
> for working under Linux and Windows GUIs. (Any other
> sugestions would be most welcome).
I recommend wxPython for cross-platform GUI design. And if you are going
to do that, I recommend the Boa Constructor IDE.
Andrew
From chchrobotics@lists.linuxnut.co.nz Tue Mar 20 09:51:07 2007
From: chchrobotics@lists.linuxnut.co.nz (Helmut Walle)
Date: Tue, 20 Mar 2007 21:51:07 +1200 (NZST)
Subject: [chbot] Odometry
In-Reply-To: <45470FCC.9030503@paradise.net.nz>
References: <45470FCC.9030503@paradise.net.nz>
Message-ID:
Apologies for probably the slowest reply ever to any posting here...
Have you taken a look at he GMR components from NXP (used to be
Philips Semiconductors)? If you can easily mount a small permanent
magnet on the end of the motor shaft or wheel axle, you can position
the GMR sensor next to it, and your encoder is ready. The only
difference is that you don't get pulses, but sine waves instead, which
should not be much of an issue in the age of readily available
microcontrollers. The advantage of this solution is that it is very
cheap, and quick and simple to set up. The GMR components are used in
many high-volume applications where component cost and reliability are
important, e.g., car accelerators. And they make nice compact and
affordable encoders...
Kind regards,
Helmut.
+----------------+
| Helmut Walle |
| walle@ww.co.nz |
| 03 - 388 39 54 |
+----------------+
On Tue, 31 Oct 2006, Carl Ranson wrote:
>
> I'd like to modify my base to correct for the slight differences in the motors
> and thought that odometry might be the way to do it.
>
> Anyone had experience with through hole type encoders (where the shaft goes
> through the encoder)?
>
> What about the home made reflective ones?
> Ta
>
From chchrobotics@lists.linuxnut.co.nz Sun Mar 25 21:02:13 2007
From: chchrobotics@lists.linuxnut.co.nz (Carl Ranson)
Date: Mon, 26 Mar 2007 08:02:13 +1200
Subject: [chbot] Lawnmower bot embraces low-tech.
Message-ID: <4606D545.9080904@paradise.net.nz>
Hey Andrew, hows your lawnmower bot going?
I found this one quite inspiring. Its a reminder that a low tech
approach can be a good way to go sometimes
http://spt06.chez-alice.fr/01/robots.htm