Joint Tutorial needs topic_name in SDF examples.

[bperseghetti]

🦟 Bug fix

Summary

This is my bad on not pushing up the final commit on adding topic_name in a few places so that the trajectory control portion works properly. 🤦🏻‍♂️

This also fixes the indents so they match when copying and pasting through tutorial.

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
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[azeey]

So what's the behavior without <topic> specified? Can we make sure that scenario works as well?

[bperseghetti]

Sure you would need to pass it to the default topic instead. Is that preferred? Or just want it duplicated in that portion?

[azeey]

I guess my question is, has the default topic changed? I ask because #2546 changed some default topics for some systems and those systems had to be updated.

[bperseghetti]

No, the default topic I don't believe has changed, the tutorial shows to publish this to control it:

gz-sim/tutorials/joint_controller.md

Line 622 in 76305df

gz topic -t "topic_name" -m gz.msgs.JointTrajectory -p '

Note that you need to have the topic name match that topic or it won't work.

And then it says to echo:

gz-sim/tutorials/joint_controller.md

Line 670 in 76305df

gz topic -e -t "/model/RR_position_control/joint_trajectory_progress"

Which once again if you change it to listen to published topic won't work. So one or the other needs to be changed/fixed to work.

[bperseghetti]

So @azeey do you want an example with only the default topic, only the "assigned topic" or one with both?