Hector mapping generates empty map

I use following launch file to run hector mapping on turtlebot. It don't gives any error also don't create any map. When I enter `rosrun map_server map_saver -f ~/mymap` mymap.pgm is light gray image. Original launch file Graph of this launch file is like this. I couldn't find the problem.  [rqt_graph](http://i.imgur.com/Hp4VDtc.png)  [tf view_frames](http://i.imgur.com/iTvkbZT.png) Latest launch file [Bag file with /scan and /tf topics](https://dl.dropboxusercontent.com/u/21699640/hector_mapping_turtlebot.bag) All of the sollutions are merged as a package at [Github](https://github.com/ormanli/turtlebot-hector-mapping)