fixed frame no tf data

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In the RVIZ window you should see the following when you click on "Fixed Frame" under "Global Options".

Fixed Frame

Frame into which all data is transformed before being displayed.

So, when your fixed frame is not there, it makes it quite difficult for RVIZ to show you much of anything (since RVIZ has nothing to project any reference frames from).

I'll point you to the tf wiki page which should be a good starting point for understanding the issue at hand.

If you click on the carrot in the box next to Fixed Frame, you should see a list of frames that are present. Selecting the correct fixed frame will fix this.

As for the "correct frame," that depends on what you're trying to visualize (if you want help deciding, just add the list of options to your question).