Hi there,

I was trying to load gazebo with a world file. But it gives following error and exits.

[Err] [Diff.cc:41] Diff plugin missing <leftjoint> element
[Err] [Diff.cc:44] Diff plugin missing <rightjoint> element
Error [Element.cc:671] Missing element description for [rightjoint]
gzserver: /usr/include/boost/smartptr/sharedptr.hpp:648: typename boost::detail::spmemberaccess::type boost::sharedptr::operator->() const [with T = sdf::Element; typename boost::detail::spmemberaccess::type = sdf::Element*]: Assertion `px != 0' failed.
Aborted

In the world file I've specified leftelement and rightelement. Why this is happening?
Also, what is meant by Missing element description for [right_joint]? I didn't find any description for joints anywhere. Can anyone provide a solution for this?

Files:
1. World file
2. Model.sdf
3. Model.config
4. Plugin

Thanks in advance!