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

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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.

Some Impressions from the Hannover Fair 2010

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Interesting designs for Rescue Robots – Part 2

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Professor Dr. Satoshi Tadokoro from the Tohoku University  presents his ASC. ASC is an search camera for usage in emergency situations and stands for Active Scope Camera. In basic it is a flexible endoscope which is able to move by it self. With the help of vibrating inclined cilia this endoscope can like a caterpillar crawl into smallest voids (>30 mm). Its maximum speed is 47 mm/s and the operating range is 8 m. This allows rescue workers to search in rubbles for victims or checking the structure of it.

The following video shows Professor Dr. Satoshi Tadokoro at the Tokyo International Fire and Safety Exhibition 2008 presenting the ASC.

During the Collapse of the Historical Archive of the City of Cologne (March 2009),  Professor Dr. Satoshi Tadokoro, Professor Dr. Robin R. Murphy (Texas A&M University), Clint Arnett (Project Coordinator for Urban Search and Rescue in TEEX), members of the Fraunhofer Institute for Intelligent Analysis and Information Systems (IAIS) were trying to support the local fire department. Therefore I was able to test the ASC which was in use during this disaster.

The ASC performs extremely well. It can crawl in a reasonable speed into the rubble and is (after a little training) easy to use. But the biggest problem is the user interface. The ASC camera system does not compensated tilting or turning if the „robot“ does flip/turn over, which happens quite often. Hence, it is hard for the Operator to keep track of the orientation. In addition the opening angle of the camera is extreme small, which does even more handicap the situational awareness.

The centenary of John R. Pierce birth

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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

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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

Interesting designs for Rescue Robots – Part 1

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Robot rescue is one, if not even the one, upcoming field for robotics. It is not new, but at present many teams and projects around the world are showing up with new ideas and solutions (e.g. NIFTi, CRASAR). So I will start to collect a few interesting approaches, and present them here on RoboBlog.

So our first candidate is the „Bari-bari II“ robot. It is developed by the Tokyo institute of technology and designed to help rescue workers by lifting heavy boulders / plates.

The capabilities are shown in the following video:

The interesting point is not that the robot can lift heavy material. That can be performed by many robots. The most robot systems that can lift material make usage of either a physical manipulator (hand or arm like) or of a blade (like we have presented earlier on this Blog: RoboPlow). But as fare as i know there is not a single one that is designed i such a way that the hole system itself if part of the lifting unit.

By side of all enthusiasm, some questions are still open:

  • The „Bari-bari II“ is presented as a tool to crawl under a plat or similar stuff. To do so it makes some maneuvers of lifting and singe off. What is about preventing against more collapses?
  • If there is now a victim below the plate, he or she will also fell the pressure of the lifting and singing. But as fare as i know, this is not wise. Victims, which are stuck should only be moved as much as needed and you shout never remove the pressure from him or here if you can not eminently support him/here by medicine. During the suck time the blood can often not circulate freely. This causes clumps of blood component. If the pressure is released the blood starts to circulate freely trow the whole body and the clumps can jam haemals. This can causes thrombosis which can lead up to death.