Hello,
I am also wondering the same. I just began with URDF today.
I did not fully explore the urdf documentation, but it did not seem so clear about the minimal configuration you would need to run a simple model without a joint_state_publisher nor a robot_state_publisher. Also, I stay curious about how to deal with partial tf trees, and tf updates from multiple sources when dealing with joint and robot publisher.
Then, I would guess only tf... provided that all the frames of your model are broadcasted by some entity(ies), it should be ok.
It seems from rviz documentation that you only need to load your urdf model as a parameter.
Robot Description: The parameter to retrieve the urdf
from. Uses searchParam() to search up
the parameter tree for the value
specified.
For example, in a launch file:
<param name="robot_description" textfile="PATH_TO_URDF_FILE" />
Should just do it. I can tell you more tomorrow when I will be integrating my brand new urdf model.
Raph