This quickly shows how a new Core type for OpenSG can be defined within Collada so that it can be loaded up. This is compatible with the Tagg3d way of creating 'tagged' selections of a geometry with corresponding metadata.
This demo makes use of the Level of Detail (LOD) node example within the OpenSG2 tutorials. It has simply been modified to be a class which accepts the filenames to load, rather than a standalone application.
Within the collada file format, the node is defined within the extra elements of the node which you wish it to appear in within your scene structure. It is defined as below:
<extra type="LOD">
<technique profile="OpenSG">
<f_high>/path/to/high/res/model</f_high>
<f_medium>/path/to/medium/res/model</f_medium>
<f_low>/path/to/low/res/model</f_low>
</technique>
</extra>
The full example can be found here
Through a couple of patches to the OSGColladaLoader (found in OSGColladaIO) we are able to process these elements and add them to the scene which is viewed.
An example showing this has been produced, which requires the following been checked out and built in order: