An example for making urdfs and visualizing them in rviz.
urdf/slidebot.urdf - A robot that has one prismatic and one rotation joint.
urdf/chain_link.urdf.xacro - An example of a xacro "utility" file containing a macro to make a link
urdf/chained.urdf.xacro - A xacro file that uses chain_link.urdf.xacro to demonstrate the use of xacro
The package contains both an XML and python launchfile. Both of these launchfiles load the robot into rviz. In a real program you would not need to provide both copies: they are for demonstration purposes only.
see_robot.launch.xml - Loads the urdf into robot_state_publisher, launches a joint_state_publisher_gui, and launches rviz
see_robot.launch.py - Loads the urdf into robot_state_publisher, launches a joint_state_publisher_gui, and launches rviz
Both launchfiles take a robot argument, allowing the user to view either the slidebot.urdf or the chained.urdf.xacro.