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How KnowRob System Work ?!

asked 2012-11-24 04:37:23 -0500

Amal gravatar image

updated 2012-12-13 05:56:40 -0500


This question may seem easy, but I want to clearly develop a plan to my project in the coming period.

1- now I have RoboEarth and KnowRob worked at all :)

2- and I get a cloud point to a cup this cloud points can be converted to an OWL file

3- and I start with knowRob System from KnowRob Wiki.

I want to ask

((1)) How to integrate this object cloud points to KnowRob Knowledge base ?

((2)) from where I have to start to define this object properties and other objects that I will work with ?! , I know that this done in Protege OWL editor but, I have to define object properties, relations with each other, relations with its environment, commonsense knowledge, task action,detection and recognition algorithms Which one I have to do first ?!

((3)) Do I need household_objects_database ?!

In sum, How this system work ?!!!

(((4))) That is an object cloud points Cloud Points

I take it using RoboEarth object recorder, The OWL description is created automatic and There was advice to not edit any thing in it. this owl describe the object

I do not understand well but this owl may extend knowrob.owl and roboearth.owl

1- How to load this to knowrob ?!

2- roboearth recorder can not detect this object I found that It can detect only

texture objects, and only one object in time. so if I use another package, how to get this OWL description ?!

3- what is the man function of knowrob.owl and roboearth.owl ?!


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answered 2012-11-25 12:13:58 -0500

moritz gravatar image

updated 2012-12-09 21:30:32 -0500

From your questions, I have the feeling that you are maybe still lacking some basic understanding of ROS, KnowRob and the underlying technology (OWL, Prolog). Without that, I'm afraid it will be very difficult to develop your own applications that go beyond the basic tutorials. At least the KnowRob tutorials are not just meant as copy&paste exercises, but rather to showcase some functionality and give you starting points from where to explore the system. This requires some basic knowledge of Prolog and OWL, and ROS in general requires some basics in Linux and Shell usage.

I'd recommend to do the OWL and Prolog tutorials linked from here Then have a look at the KnowRob tutorials again and try to actually understand what's happening. Learn to use the graphical tracer in Prolog and follow the inference step by step.

Also have a look at the KnowRob-related publications ( The code examples in the papers are not always directly copy&paste-able, some are simplified or depend on a special launch configuration, but the papers will give you an idea of what is possible and what are difficult problems.

I'd very much recommend a more structured approach, just taking arbitrary queries from different wiki pages and trying to execute them just won't lead anywhere. And this question shows that some deeper understanding is needed (e.g. I have no idea what you mean with "convert a point cloud to an OWL file", and the household_objects_database does not have much to do with KnowRob apart from the fact that it's used by the tabletop_object_detector that can be interfaced with KnowRob).

EDIT: 1) The auto-generated OWL file contains the bare minimum to make that object find-able in the RoboEarth DB, i.e. it describes that this instance of object recognition model can be used to recognize that kind of class. You can load that file to KnowRob using the owl_parse predicate. If you look at the OWL file, you will see that it does not described other object properties (how should it get this information anyway?), so you'll need to create it. As I said, this requires some understanding of what OWL is and how you describe knowledge in it.

2) All image feature based object detectors are good at textured objects and worse at untextured objects. If you use another recognizer, you'll need to create the OWL file yourself.

3) There is no man function for these OWL files, but you can read the files themselves.

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you are right I know that I have not more knowledge. I just start from one month ago and I try to gain it by reading,trying copy/past and see what is going on,and asking here,but I can not keep reading without determining nearby target. I mean that I want to gain this basics while going on the proj

Amal gravatar image Amal  ( 2012-11-26 07:22:50 -0500 )edit

see my Q edit please

Amal gravatar image Amal  ( 2012-12-02 08:34:37 -0500 )edit

OK, Can I use RoboEarth to get this Cloud Points and OWL, Then use another package to do Processing this C.P. ... Do you suggest any ?!


Amal gravatar image Amal  ( 2012-12-13 05:58:18 -0500 )edit

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Asked: 2012-11-24 04:37:23 -0500

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Last updated: Dec 13 '12