how to use Umbilical Plugin?

[robotian]

Hi,

Thank you for a great simulation stack. I'm still getting familiar with many packages and have a question. So this is not a issue, but could find any other place to ask about. It seems like the simulator has a Gazebo plugin 'libumbilical_plugin.so' according to a file '/uuv_gazebo_worlds/models/umbilical/model.sdf.'
I was trying to spawn this model in Gazebo, but it gave me a error as below.

Registered UmbilicalModel type Berg
gazebo::UmbilicalPlugin::UmbilicalPlugin()
Error [Element.cc:770] Missing element description for [umbilical_model]
gazebo::UmbilicalModel* gazebo::UmbilicalModelFactory::CreateUmbilicalModel(sdf::ElementPtr, gazebo::physics::ModelPtr)
Segmentation fault (core dumped)

I could not find any example related to this plugin. Can anybody provide some information about what the plugin does and how to use?

Thank you

MK