I think it can also be called that way

I don't understand

"For code block block given below"

I also don't see that string in that page, can you elaborate?

I think it can aslo be called that way

On Transforms in Navigation2 in the below paragraph abbreviation for URDF

All other statically defined transforms (e.g. base_link => base_laser, base_link => wheels, wheels => IMU, etc) is what we will be talking about for the rest of this guide. This transformation tree is used by Nav2 to properly relate the information from sensors or other frame of interest to the rest of the robot. The transformation between these two coordinate frames is usually provided to Nav2 through the Robot State Publisher and the Universal Robot Descriptor File (URDF) . In cases where there are more sensor coordinate frames on your platform, then a transform tree from base_link to each sensor coordinate frame needs to be published.

"For code block block given below"

On Writing The URDF

For the code block block below, we access the base properties from the robot constants sections we defined before using the ${property} syntax. In addition, we also set the material color of the main chassis to Cyan. Note that we set these parameters under the tag so they will only be applied as visual parameters which dont affect any collision or physical properties.

What I meant is that I don't understand your suggested change. Should we not be expanding the abbreviation to explain what it stands for?

For the code block block below,

Weird, that didn't come up on my grepping before. Will fix. #704

What I meant is that I don't understand your suggested change. Should we not be expanding the abbreviation to explain what it stands for?

Now I get that, because you're explaining what URDF really is in the next section.

Weird, that didn't come up on my grepping before. Will fix. #704

Glad you got that and fixed it.