Function blocks for the BRICS_3D library

Overview

A function block is a computational entity that performs an arbitrary computation on the data stored in a world model based on the Robot Scene Graph (RSG). It consumes and produces scene graph elements. Algorithms for estimating near future states are one example of such a computation. A function block can be loaded as a plugin to the RSG and is executed on demand. This allows to move the computation near to the data to improve efficiency of the executed computations.

The current implementation of the RSG is part of the BRICS_3D library.

• All elements in the RSG are uniquley adressable via thier IDs. These IDs serve as input and output for a function block. The ports called inputDataIds and outputDataIds are used to transfere this information.

  Multibple function blocks can be chained up if the output port of one block is connected with the input port of another function block. This allows to create processing chains by combining individual of function blocks.

• To obtain access to the data of the handle of world model is passes as configuration parameter wm_handle. This handle is not supposed to change during runtime.

Dependencies

• BRICS_3D library. Installation instructions can be found here: http://www.best-of-robotics.org/brics_3d/installation.html
• microblx library. See: https://github.com/kmarkus/microblx

Here is a summuary on how to install microblx on Ubuntu (12.04)

Dependencies:

	sudo apt-get install clang

	wget luajit.org/download/LuaJIT-2.0.2.tar.gz
	tar -xvf LuaJIT-2.0.2.tar.gz 
	cd LuaJIT-2.0.2
	make
	sudo make install
	sudo ldconfig

Installation of the actual microblx library:

	git clone https://github.com/kmarkus/microblx.git
	cd microblx
	git checkout dev # you might want to skip this step
	source env.sh 
	make
	echo "export UBX_ROOT=$PWD" >> ~/.bashrc

Compilation

 $ mkdir build
 $ cd build 
 $ cmake .. -DCMAKE_CXX_COMPILER=/usr/bin/clang++
 $ make 
 $ cd ..
 $ echo "export FBX_MODULES=$PWD" >> ~/.bashrc

Usage

To start the example do the following:

sh start_demo.sh 

The system will be initialized. To actually start it go to the web interface at localhost:8888 and click on all dark green start buttons.

Licensing

This software is published under a dual-license: GNU Lesser General Public License LGPL 2.1 and Modified BSD license. The dual-license implies that users of this code may choose which terms they prefer. Please see the files called LGPL-2.1 and BSDlicense.

Impressum

Written by Sebastian Blumenthal ([email protected]) Last update: 06.06.2014