At its heart, it is not hard to see that a SDF model is a file that describes the kinematics of a system. It indeed contains all the information (and some more) needed to configure Rock's transformation handling system.

And that is what happens when one uses use_gazebo_model. The profile's transformer is automatically configured, using all the model's links as frames and the information from within the SDF file to configure static transforms. Additionally, all the link transformation devices generated with sdf_export_link are properly annotated with frames.

And all is good.

But then what happens in other profiles ? How can we make the same information available since it is not recommended to use_gazebo_model the same model in different profiles ?

Also, how do we reuse the same information to configure the transformer in our live systems, while avoiding the dependency on gazebo ?

Without further ado

Using SDF-Derived Transformer Configuration Across Profiles

The Syskit integration for the transformer provides the use_profile_transformer stanza, which allows to configure a profile's transformer using the data from another. Just use this at the top of any profile that requires the information that your Base profile has:

module YourVehicle
    module Profiles
        profile "Control" do
            use_profile_transformer Base

Using SDF-Derived Transformer Configuration in Live Systems

use_gazebo_model has a non-gazebo, SDF-only equivalent, use_sdf_model. Adding use_sdf_model at the top of a profile does the transformer configuration, but without any of the device definition that use_gazebo_model does.

If you wish to use this, you still need to provide a world file. This file is loaded with Syskit.conf.use_sdf_world instead of Syskit.conf.use_gazebo_world. The require does not change.

To avoid installing all of gazebo and the gazebo plugins, while still being able to load rock_gazebo/syskit to get use_sdf_model, one has to exclude the simulation packages while simultaneously adding simulation/rock_gazebo explicitly in the layout. In your autoproj manifest, do something along the lines of:

   - my.main.metapackage
   # Force-add simulation/rock_gazebo despite the simulation/.* exclude rule
   - simulation/rock_gazebo

   - simulation/.*