Sunday 30 October 2011

MAPS FROM STAGE SIMULATIONS IN ROS

SLAM USING STAGE'S WANDER CONTROLLER IN ROS

SLAM, Simultaneous Localisation and Mapping; using simulations in stage/stageros  to map the environment based on sensor readings from a mobile robot in the 'wandering' mode may be done as follows;

#.1 - Start an instance of the master in a terminal window

roscore
 
#.2 - Start the stage/stageros simulation in a new terminal window 

rosrun stage stageros /path/to/.world file 

The world file employs stage controller 'wander' hence the robot starts moving immediately and is in a wandering mode. 

#.3 - Start gmapping in a new terminal window 

rosrun gmapping slam_gmapping scan:=base_scan

#.4 - Start map server in a new terminal window 

rosrun map_server map_saver 

The map will get saved in the directory from where the command for map_server is issued as a pgm file.

Run the simulation sufficiently long enough for a good map. While the simulation is running, on running rxgraph in a new terminal window one may see the following graph for the ROS nodes.



SAMPLE OUTPUTS

#.1 


#.2 

 
#.3

 
NOTE : Simulations done in ROS 1.4.9 diamondback

REFERENCES
1) I thank Mac at ROS for his suggestions
2) This blogpost went to be motivation for a ROS tutorial - http://www.ros.org/wiki/stage/Tutorials/MakingMapsUsingStagesWanderController


Friday 28 October 2011

ROS TUTORIAL, STAGE CONTROLLERS

My first contribution to the ROS community, Tutorial on Introduction to Stage Controllers

Codes for the tutorial are available here

Wednesday 26 October 2011

VOLKSBOT

VOLKSBOT@PLAYER/STAGE

While browsing the web, I came across a very interesting model in player/stage, Volksbot. The sheer complication of the robot and its depiction in the stage model impressed me.
 



The model was designed for Stage 4.X.X, Brian was kind enough to send the model through to my email and I was able to modify it to suit Stage 3.X.X. 

CODES
  1. The codes for the simulation are available here