Hi, I'm trying to visualize the URDF models of the nxt_robots (robot.urdf
files on each package) with the display.launch program from the
urdf_tutorials stack, but I don't seem to be able to do so, it keeps
crashing all the time:

started core service [/rosout]
> process[joint_state_publisher-2]: started with pid [2754]
> process[robot_state_publisher-3]: started with pid [2759]
> process[rviz-4]: started with pid [2762]
> Traceback (most recent call last):
>   File
> "/home/capelare/ros/urdf_tools/joint_state_publisher/joint_state_publisher",
> line 208, in <module>
>     jsp = JointStatePublisher()
>   File
> "/home/capelare/ros/urdf_tools/joint_state_publisher/joint_state_publisher",
> line 25, in __init__
>     robot = URDF().parse(description)
>   File
> "/home/capelare/ros/urdf_tools/urdf_python/src/urdf_python/urdf.py", line
> 506, in parse
>     base = xml.dom.minidom.parseString(xml_string)
>   File "/usr/lib/python2.7/xml/dom/minidom.py", line 1924, in parseString
>     return expatbuilder.parseString(string)
>   File "/usr/lib/python2.7/xml/dom/expatbuilder.py", line 940, in
> parseString
>     return builder.parseString(string)
>   File "/usr/lib/python2.7/xml/dom/expatbuilder.py", line 223, in
> parseString
>     parser.Parse(string, True)
> xml.parsers.expat.ExpatError: not well-formed (invalid token): line 2,
> column 12
> [joint_state_publisher-2] process has died [pid 2754, exit code 1].
> log files:
> /home/capelare/.ros/log/b0629bba-0bad-11e1-93ed-001d4ffc607c/joint_state_publisher-2*.log


That's what I get on the Terminal. Then rviz opens and displays all the
meshes on the origin. Any ideas? Too many joints, maybe? The robot.urdf
file passes the check_urdf tool, so I guess the syntax is OK.
BTW, display.launch works fine with the urdf files I made following the
urdf_tutorials, if you're wondering.

I'm still getting used to ros, urdf, rviz... and I tried to make this work
by myself, so maybe this is the stupidest problem ever, but I'm totally
lost.

Thanks for your time,
Miguel :)