This library defines the main entities & relations of the X-Rock project(s). XTypes are a generic type of objects. The speciality of this type is that it has a standardized type definition that allows to add properties and relations to other XTypes.
X-Types was initiated and is currently developed at the Robotics Innovation Center of the German Research Center for Artificial Intelligence (DFKI) in Bremen, together with the Robotics Group of the University of Bremen.
To represent any hardware and software component of modular robots we developed X-Types. They provide an easy to use representation, with C++ and python interfaces. X-Types can be stored, read and maintained in a database see (the xdbi package).
A ComponentModel describes a type of entity like a blueprint, a Component is then it's instantiation. The same principal applies for InterfaceModels and Interfaces, they define connections between Components.
A connected set of Components can be stored and reused as new ComponentModel.
Modules are unique Components.
X-Types also provides ExternalReferences which offers the possibility to annotate ComponentModels with links to other external data sources.
Example: You have a robotic arm with three revolute joints. All joints use the same motor. In the database you already have defined a ComponentModel which represents it in general. Also you have defined an InterfaceModel which represents the flange of the motor and specified that the motor has two Interfaces of this InterfaceModel The same you have done for the links in between. Now we can instantiate the motor-ComponentModel to three motor-Components and the links as well. Each motor-Component is annotated with the necessary information e.g. an ID or a zero-pose. Via their Interfaces we now specify how everything is connected.
This new setup can now be stored as ComponentModel and be used in bigger assemblies.
As soon as we really build this robot. Each Component has to be realized by a Module. The Module has the same properties as the Component but relates to one single entity.
If you have two of those arms, both have the same Components, but not the same Modules as e.g. each motor has it's own controller with it's own MAC-adress.
X-Types make use of the X-Types-Generator and are thereby compatible with all other types generated using the xtypes_generator.
You can either use the python or the C++ interface to use and maintain your X-Types. In the following you find a basic python example.
import xtypes_py
cm = xtypes_py.ComponentModel()
cm.name = "Motor"
cm.domain = "HARDWARE"
...
im = xtypes_py.InterfaceModel()
im.name = "Flange"
im.domain = "HARDWARE"
# now we state that our motor has two flanges
im.instantiate(cm, "base")
im.instantiate(cm, "drive_side")The usage in C++ works analogous.
Just use #include <xtypes/xtypes.hpp> to have everything available.
For direct usage without implementation consider using the X-Rock-GUI.
- CMake >=3.10
- X-Types-Generator
- libgit2
- python3
- XDBI
NOTE: The scripts that are part of XTypes assume a UNIX based system
Either via CMake:
mkdir build
cd build
cmake ..
make installAs soon as this package is integrated into one of our package_sets, you can of course also use autoproj's amake
After building you can generate the API documentation using make doc in the build directory.
The API documentation is generated into build/doc/html.
cd build
make cpp_test # for testing the C++ interface
make py_test # for testing the python interfaceYou'll find further information on the here defined types in doc/Entities.md