Free German NXC Tutorial

Not eXactly C is a high-level programming language for the Lego Mindstorms NXT. NXC, which is short for Not eXactly C, is based on Next Byte Codes, an assembly language. NXC has a syntax like C.

There is a new version of the NXC Tutorial available at the Roberta Homepage. It is an extended german version of the tutorial original based on the work of Daniele Benedettelli.

You can download the german tutorial for free here: http://roberta-home.de/de/was-bietet-roberta/roberta-reihe/nxc-tutorial

The English original version is available here: http://bricxcc.sourceforge.net/nbc/nxcdoc/NXC_tutorial.pdf

http://roberta-home.de/sites/default/files/images/Tutorial.thumbnail.JPG

K-Dimensional space-partitioning data structure library for C++

On of the most common question by handling large data sets is „How to represented the data?“ and of course the answer is versatile. One of the most used solution is a tree like structure, organized by at least one sorting criteria.

KDTree++ is a c++ library which is supporting this feature. KDTrees are allowing to sort data by ‚k‘-Dimensional sorting criteria and the library implements a template based realization. KDTree++ is published under Artistic License 2.0.

Update: I was trying to use KDTree++ in on of our projects on Three-Dimensional perception and Point Clouds analysis. Therefore i was adding roundabout 30.000 Points (x,y,z-coordinates plus some extra informations) into such a tree. The first feeling was quiet positive. It was fast and did not consume that much resources. But by using the search functionality, provided by KDTree++  i was shocked. Every time i was placing a query the memory consumption did rise up dramatically, and even worse, it was staying that high. After investigating the KDTree code i figured out that the library does on each query create a copy of the found items and returns them. Unfortunately those items are never deleted and if i try to deleted them by my self the library produces a segmentation fault. So, summing up i would say that these library is really powerful, but bad documented and seems to have some serious bugs.

The centenary of John R. Pierce birth

John Robinson Pierce was born in March 27, 1910 Des Moines – Iowa and died at April 2, 2002 in Sunnyvale – California. During his life time was he an expert in the fields of radio communication, microwave technology, computer music and psychoacoustics. His team developed in the year 1949 the first transistor. This pioneer work allowed the building of modern digital computers and robots, as well as nearly all digital components of our every day life.

For those that would like to learn more about this pioneer we recommend flowing artikels:

So, RoboBlog says happy birthday and thank you.

Adhesive foil/cover for Lego Mindstorms NXT available

Ever wanted to individualize your NXT a bit more?

Now you can buy the Roberta adhesive foils for Lego Mindstorms NXT (design by Ashley A. Green) at Technik LPE and coulourise your NXT the way you want. The foils are wipeable, heavy-duty and removable.

See:
http://roberta-home.de/de/aktuelles/|neu|-roberta-nxt-klebefolie

http://www.shop.lego-in-der-schule.de/Uebersicht?sparte=10

FAIR Libary is online

As we have already reported is the „Fraunhofer Autonomous Intelligent Robotics Devices“ Library now open source and available at the sourceforge project „OpenVolksBot„. In addition we can know report some more details on it.

  • The FAIRlib is now organized as several Eclipse-Project (fairAlgorithm, fairCore, fairDevices, fairGraphics, fairTestAlgorithm, fairTestCore, fairTestDevices and fairTestGraphics). This allows an easy extending and compiling the projects and minimizes the cross dependencies.
  • The dependences  are listed in the ReadMe and can be auto installed by using the script „apt-get-fair“
  • A way of easy installing is given by the script „install-fair
  • The current version is tested on the Ubuntu 9.10 (64-Bit) ,  but will also work on other OS (by side of auto solving the dependences)
  • Fair is published under the CC-by-sa-nc License .

So now we all can reuse and cooperated in a create library, instead of reinventing the „wheel“ again and again. 😉