How to write a tf publisher for laser scanning

edit

Hey,

I got a question regarding the tf publisher. I try to visualize my Hokuyo laserdata in Rviz. I dont have a robot yet or something, the Hokuyo is just standing on the desk :) So I wrote a little publisher for the Hokuyo to publish the laser data and now I want to visualize them in rviz. But for now Rviz is complaining about Global Status: Fixed Frame "Fixed frame...does not exist" and so on. So my approach is to write a publisher so I can just select my frame from the laserscanner from the dropdown menu in Rviz. But for now I cant just write a publisher using this tutorial TF Tutorials. I maybe just don't get or understand it :) But I hope someone of you can help me.