.. _ccainterface:

=============================
 Oncilla Component Interface
=============================

For a CCA application the Oncilla robot is represented by a set of resource
nodes and the synchronizer, accessible to the :ref:`CCA component architecture <cca>`
or via the :ref:`RSB middleware <rsb>`.

.. image:: images/OncillaAPI.png
  :width: 450px
  :align: right
  :target: _images/OncillaAPI.png
  :alt: Oncilla Component Interface (click to enlarge)

The basic spaces provided by the Oncilla component interfaces are depicted in the
image on the right (click to enlarge). The core robot component provides four
spaces for the three angles of each leg. It listens for position command on four
spaces for the legs.

Additional supervisors (only implemented for the simulation  backend) provide
the robot pose in world coordinates, cartesian position of the feet and allow
to reset the world (only in simulation, of course ;).

|project| provides the helper object ``CCAOncilla`` that sets up the resource
nodes, the synchronizer and a working default configuration. This can be used as
basis for custom configurations. The configuration and the available ports are
detailed in :ref:`oncilla`.

Resource Nodes
==============

The Resource Nodes are implemented in RCI and wrapped in CCA so that the rich
proprioceptive feedback of the robot is available as data-flow on the one hand.
On the other hand commands can be sent to the robot via data-flow by sending
commands to the resource nodes.

The actual specification of the resource nodes is described in the
:ref:`liboncilla` documentation. Documentation of the CCA wrappers can be found
here:

#. :doc:`ccaoncillal0` - The L0 joint of Oncilla	
#. :doc:`ccaoncillal1l2` - The L1 and L2 joint of Oncilla
#. :doc:`ccaoncillal3` - The L3 joint of Oncilla	
#. :doc:`ccaoncillal4` - The L4 joint of Oncilla	

Synchronizer
============

The CCA synchronizer component wraps the actual synchronizer and therefore cares
for updating the resource nodes and synchronizing the with the robot in the
timing given by the CCA application or configuration.