Hi,
I am trying to build a map using slam_gmapping. My platform is ActivMedia MobileRobots Powerbot equipped with sonar sensors and SICKLMS laser range finder. I am using the `ROSARIA` package to interact with the robot and to get the odometry data. Then I am using `sicktoolbox_wrapper` package in order to interface with the laser range finder. I have tested each node separately to make sure that the data I want is being published over the respective topics. I tested this with ROSARIA by running `rostopic echo /RosAria/pose` and also by writing code to subscribe to that topic. Similarly I ran `rostopic echo scan` to see that the laser range finder is really working and I can see the data being streamed. I also tried to visualize it on `rviz` but I got an error saying that the frame `[laser]` does not exist. I don't know how to fix this but since I saw the data being publish over `rostopic` I assumed that the laser scanner was set up and ready to be used.
So I followed [this tutorial](http://wiki.ros.org/slam_gmapping/Tutorials/MappingFromLoggedData) and built a bag by moving my robot around the room. The bag was created "successfully" since no errors had been given. At this point I wanted to verify that all the nodes were running appropriately and the right publishing and subcribing was being made. So I ran `rqt_graph` and got this: [C:\fakepath\setup rqt.png](/upfiles/14225269666729206.png). From what I know of ROS, everything is set up according to the tutorial, having the `slam_gmapping` node being subscribed to both `/scan` and `/tf` (this is the only difference from the tutorial: in the tutorial `base_scan` was used while my topic from sicktoolbox_wrapper was just `scan`).
I thought that having all this set up would result in a successful build of the map. However, when I ran gmapping and replayed the bag that I had recorded I got this error:
Warning: TF_OLD_DATA ignoring data from the past for frame base_link at time 1.42253e+09 according to authority /play_1422525800501358444
Possible reasons are listed at http://wiki.ros.org/tf/Errors%20explained
at line 260 in /tmp/buildd/ros-hydro-tf2-0.4.12-0precise-20141016-1214/src/buffer_core.cpp
When the bag stopped replaying and I attempted to save the map, no map was saved and it just kept "Waiting for map". Also, during the process of 'building' the map, I tried to visualize it on rviz but again, I got a warning message telling me "Map is not found".
Can anyone help me identify the fault and explain what is going on? Thanks!
EDIT
From what I can see from this `rqt_graph` [C:\fakepath\slam_gmapping.png](/upfiles/14225331029416947.png) is that the node slam_gmapping is publishing on the topic `/map`. I have added a Map on `rviz` and set its topic to `/map` but in the Status I'm getting a Warning saying: No Map Received. [C:\fakepath\Rviz Slam_gmapping.png](/upfiles/14225331293912349.png)How is this possible?
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