gmane.comp.hardware.lego.robotics

Brickworld 2013

Adam Tucker — 2013-02-15T21:47:53

Good afternoon everyone,

If you have not heard, Brickworld 2013 will be held at a new home - The
Renaissance Hotel & Convention Center in Shaumburg, IL.  This move is in
response to the attendees desire to hold the event in a single room.  We will be
starting this year with a 50,000 square foot room for the fun.

This will be an entirely new and fun experience for all the attendees.

You can learn more at <http://www.brickworld.us Brickworld's web site>.

Also, Geek Nation Tours will be hosting a special tour to the event if they
generate enough interest.  Stay tuned as they will post additional information.

As always, we look forward to seeing everyone at the event in June.

Warm Regards,
Adam, Bryan and the entire Brickworld Team

Re: LEGO announces latest MINDSTORMS verion: EV3

Abner — 2013-01-08T04:22:36

snip

Already mention the Mindstorms EV3 Press Release information in Mediawatch,
General, Lego and Robotics newsgroup.

-Abner

Re: LEGO announces latest MINDSTORMS verion: EV3

Abner — 2013-01-08T04:21:54

snip

Already mention the Mindstorms EV3 Press Release information in Mediawatcth,
General, Lego and Robotics newsgroup.

-Abner

LEGO announces latest MINDSTORMS verion: EV3

David Schilling — 2013-01-08T03:49:41

In case no one has noticed, earlier today LEGO announced their newest MINDSTORMS
version at CES. This version is called the EV3, and will be released later this
year.

I'll let you do your own web searches for official announcements, pictures, and
videos.

--
  David Schilling

Re: Kalman Filter on the NXT

Claude Baumann — 2012-12-29T10:38:16

That's what the Kalman filter is about. One of its important application areas
is navigation (from rockets to ships and robots). In our example, we try to
develop the implementation for a robot driving in one only dimension, the
x-axis. And the model is given by Galilei's law of motion, written as difference
equations with i as the time-dependent index:

x(i) = x(i-1)+ s(i-1)*dt + a*dt^2/2
s(i) = a*dt

where x=displacement, s=speed (both system states), dt=time tick
and a=acceleration (due to external forces)

So, at any moment, if we have an initial estimation of both state variables, we
can predict, where the vehicle will be next. This prediction is error-prone,
because it obviously depends on the quality of our starting estimation and some
noise due to irregularities of the environment and the robot caracteristics.
Now, if your robot is supposed to move in a more or less even plane, then you
can admit that the acceleration is a=0. Any non-zero component can be seen as
part of the noise. (Because we expli

RE: Kalman Filter on the NXT

Bruce Boyes — 2012-12-28T23:09:26

I have a memory from attempting to use the Kalman filter, starting with a
model, and working through the math, that it made some assumptions, which
importantly included an originally good sensor signal subsequently clouded
by noise. Kalman can recover most of the original signal. We modeled this on
the PC and could see good efficacy in that circumstance. 

But in our case we had a noisy sensor, and in this case my memory was that
the Kalman filter was not any solution. In our particular case we are trying
to use a (non-Lego) DC motor commutator as a tachometer, while the motor is
also being driven. We pause driving for long enough to capture some
commutations while the motor is coasting. We concluded that the quality of
the commutator was so low due to sloppy manufacturing that this corrupted
both the predictability of driving and sensing. Worse, this slop was not
consistent across many motors, so we could not make a universal model for
it. What I don't remember is how we concluded that there was a differenc

Re: Kalman Filter on the NXT

David Koudys — 2012-12-28T18:12:36

All over my head.

But, if and when I actually get my GPS robot working, I'm going to look this up
again.

Dave K

Re: Flying LEGO

David Koudys — 2012-12-28T17:02:50

That's really cool!  Another aspect of this hobby that people can delve into.

Dave K

Kalman Filter on the NXT

Claude Baumann — 2012-12-28T12:58:05

The Kalman Filter may be perceived as a discouraging, almost occult calculation
method. Many do apply the filter just by following some "cooking recipes", and
they don't care much about the internals. However, if the filter is well studied
and adapted to the current problem, then --tada-- things may appear very easy...
and its use on the NXT is no secret anymore.

If you want to learn more about the Kalman Filter, then have a look at its
implementation into a simple application on www.convict.lu/blog/?p=230. A
vehicle drives don't the inclined plane, and wants to exactly know its speed and
position. It is equipped with an accelerometer, a tachometer -made of a LEGO
legacy motor, used as a DC-generator- and a legacy rotation sensor. Every sensor
has its own trouble of accuracy and precission:

- the accelerometer is caracterized by an important drift, making computation of
the speed, and position (by integration) very error-prone
- the tachometer has a significant ripple due to the motor coils.
- the rotation

Flying LEGO

Michael Huffman — 2012-12-27T22:20:57

A LEGO Arducoptor:

http://youtu.be/HSWX3uH5MEM

--Mike.

Danish LEGO Group supports World Robot Olympiad

Abner — 2012-11-09T12:19:59

[Danish LEGO Group supports World Robot Olympiad]

From November 9-11, 2012, [World Robot Olympaid 2012 is held in Kuala Lumpur,
Malaysia. For several years in a row, Danish LEGO Education has been a main
sponsor of World Robot Olympaid (WRO). This years WRO theme is social robots -
robots that can be a part of our social life].

Malaysia is having the honor of hosting the World Robot Olympiad 2012. World
Robot Olympiad (WRO) is a worldwide robotics competition that has proven
successful in raising students interest in science, technology and robotics
globally. It has given students an accessible, equal playing field to gain,
learn and test their knowledge at the world stage. It gives them confidence in
their abilities to use technology in an innovative way and experience how it is
relevant to their future.

WRO works closely together with their sponsors, who share the same values and
goals about children and education. LEGO Education has been a main sponsor of
WRO for seven years in a row including

Re: "Casemate explorer" project resumed

Claude Baumann — 2012-10-27T15:47:49

<http://www.convict.lu/Jeunes/RoboticsIntro.htm>

"Casemate explorer" project resumed

Claude Baumann — 2012-10-27T15:44:13

Last academic year we started an ambitious project with the LEGO compatible
<http://www.tetrixrobotics.com/ Tetrix> robotic kit:

[<http://en.wikipedia.org/wiki/Casemate Casemate> Explorer]

As the City of Luxembourg is undermined by casemates, which are vaulted chambers
of the old fortress, our robot should be able to traverse such a gallery, and
draw a map of the path taken.

Note that we reshaped our known web-site:

<www.convict.lu/Jeunes/RoboticsIntro.htm>

You'll find a News section, a Blog and a Sticky space with all of our old
projects. You will be able to follow the Casemates project in the blog section.

Re: Raspberry Pi and Berry Box The Transparent Case

Jeff Findley — 2012-10-18T15:07:02

I just received my Raspberry Pi (lastest revision which is Rev 2 with 512 MB of
RAM) and will be building a Lego case for it.  There are several Lego case
designs out there for public consumption:

Lego case which can be ordered (instructions online)
http://www.thedailybrick.co.uk/lego-sets/custom/lego-custom-raspberry-pi-case.html

Bizs LEGO case  the Boreatton Scouts hit Germany.
http://www.raspberrypi.org/archives/1354

Two different Lego RPi Cases on elinux.org (and lots of other cases)
http://elinux.org/RPi_Cases#Lego_Case

Raspberry Pi Lego-crust cluster (64 Pi's with Lego cases)
http://www.theregister.co.uk/2012/09/12/raspberry_pi_supercomputer/

Re: Eureka! Problem Solving with LEGO Robotics

Abner — 2012-09-08T10:30:34

<http://www.ntspress.com/ ntspress.com>

Eureka! Problem Solving with LEGO Robotics

Claude Baumann — 2012-09-08T07:16:24

I'm happy to announce my book :

[Eureka! Problem Solving withe LEGO Robotics]

<link
<http://www.ntspress.com/wp-content/plugins/magic-fields/thirdparty/phpthumb/phpThumb.php?w=150&h=200&zc=C&src=http://www.ntspress.com/wp-content/files_mf/baumann_cover.jpg>>

The book is intended for interested readers who wish to tackle demanding
challenges from science and technology, and who want to be challenged by LEGO
robotics because of personal interest, or because they wish to encourage their
children in STEM activities.

Available at <link www.ntspress.com>

Re: Question about NXT rechargeable battery

Jetro de Chateau — 2012-05-17T19:14:50

It never hurts to ask LEGO customer support...

Re: Question about NXT rechargeable battery

Ross Crawford — 2012-05-16T02:52:04

Hi Frances,

Unfortunately, it may not be recoverable. Rechargeables can lose their ability
to hold a charge if left unused for long periods.

Having said that, I generally leave my NXT rechargeables attached, sometimes for
long periods, and they are both still working well after several years, I used
one of them to power my dish for 2 days at BV12 (although I was switching the
NXT off while I was away from the exhibit).

ROSCO

MinuteBot Base

Jetro de Chateau — 2012-05-14T19:23:24

There is a great project for creating a technic/MINDSTORMS baseplate on
Kickstarter that could be a great classroom or hobbydesk testbase as well as
provide a sturdy base (or side) for many Robotics projects.

Have a look at the <http://www.kickstarter.com/projects/37801615/minutebot-base
MinuteBot Base website> to see what it is all about.

<<http://i1206.photobucket.com/albums/bb442/SEQINETIC/MinuteBot/MinuteBase_partview2.png>>

Question about NXT rechargeable battery

Frances Schroeter — 2012-05-14T10:09:47

I bought a rechargeable battery for my NXT and was very happy with it.
However, I have ended up not using the NXT for some months and the rechargeable
battery was left in the NXT.
This weekend, I went to recharge the battery, it has been on the charger for two
days now and the battery is still flat. The green light comes on on the battery
indicating that it is charging. 
Any ideas what the problem is, and what I can do to get the battery to recharge?

Re: Raspberry Pi and Berry Box The Transparent Case

Jacob Sparre Andersen — 2012-04-13T07:02:08

Jeff Findley wrote:


Initially (at least) the Pi comes without a case, so I expect it is just
a matter of building around it so it doesn't rattle too much.  I haven't
received mine yet, but I'll take a moment to see how well a pure LEGO
case can work.

It feels a little bit like waste to use a Pi for embedded systems
considering that it has HDMI output and can run a 1080 lines video
display. - But I can't find anything as cheap with the same computing
power.

Play well,

Jacob

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<http://lego.sparre-andersen.dk/Pier_17/ <http://lego.sparre-andersen.dk/Pier_17/illustration.png>>
<http://lego.sparre-andersen.dk/CityXers/Postbil/ <http://lego.sparre-andersen.dk/CityXers/Postbil/illustration.jpeg>>
<http://lego.sparre-andersen.dk/Antikken/Romerriget/Circus_Maximus/ <http://lego.sparre-andersen.dk/Antikken/Romerriget/Circus_Maximus/illustration.jpeg>>
<http://lego.sparre-andersen.dk/By/Faroese_landscape/ <http://lego.sparre-andersen.dk/By/Faroese_landscape/illustration.jpeg>>