1.ImportError: No module named beginner_tutorials.srv
解决：
cd ~/catkin_ws $ source devel/setup.bash $ rosrun beginner_tutorials add_two_ints_server.py
2.roscreat-pkg: command not found
catkin_create_pkg smartcar_description urdf
3.the config file '/opt/ros/indigo/share/urdf_tutorial/urdf.vcg' is a .vcg file, which is the old rviz config format.
将launch文件最后vcg改成rviz;
<node name="rviz" pkg="rviz" type="rviz" args="-d $(find urdf_tutorial)/urdf.rviz" /> </launch>