Features of Xacro

Xacro is the XML macro language for ROS. Xacro provides a set of macro operations to replace some repetitive statements with shorter, concise macros that will expand into full XML statements when processed. Xacro can be used with any XML document, but is most useful with long, complex URDF files. Xacro allows you to create shorter and more readable XML files for the robot URDF. Xacro provides advantages in many different areas:

• Properties and property blocks: If repeated information is used in a URDF/SDF file, the <property> tag can be used to specify these constant values in a central location. Property blocks are snippets that can contain one or more XML definitions. These are typically parameters that can be changed later. Properties and property blocks are usually declared at the beginning of the file, although this is not required. They can be found anywhere in the XML file at any level. It does not matter whether the property declaration is before or after its...